How to Lay Concrete Kerbs Along a Driveway

Laying edging kerbs is a simple DIY job with this guide!
© Eugene Brennan

Give Your Driveway a Crisp, Clean Look

Edging a lawn or driveway gives it a crisp, clean look and helps the eye to define the boundary between lawn or flower beds and the harder look of the concrete, stone or tarmac (asphalt) surface of your drive. There are lots of options, including brick and cut stone, but in this guide, we’ll look at an inexpensive method using concrete edging stones. These are reasonably easy to install if you have basic DIY skills.

Tools You’ll Need

• Shovel for mixing concrete
• Cement Mixer (optional) for mixing concrete quicker and more thoroughly
• Level for checking edging is plumb
• String line and canes, bars, or pegs for supporting line
• Mallet or alternatively builder’s hammer for tapping stones into place

Materials You’ll Need

• Kerb stones
• Ballast (mixed aggregate) or alternatively small stone and building sand
• Portland or flyash cement

As an alternative to making your own concrete, you can buy ready-made drymix.

© Eugene Brennan

Overview

Kerbs are supported by a bed of concrete on the underside and haunching or supporting concrete at the rear. Since most of the pressure will be from vehicles and human traffic on the driveway surface, this prevents the stones from being pushed backwards into flowerbeds or the lawn. You can also use concrete at the front for added support or back fill with stone.

I deal with 2 inch by 7 inch edging in this guide. Thicker kerbs with a wider base are normally used for a driveway, but in my case the stones are under bushes at the edge of the drive and unlikely to be driven on. You can also use thin edging stones like these as a trim on the boundary of a lawn.

Procedure

Follow these steps to lay your stones

Step 1: Dig a Trench

Dig a trench about 8″ (200 mm) wide by 7″ (175 mm) deep. A 2″ to 3″ (50 mm to 75 mm) bed of concrete is sufficient for laying light edging kerbs, so that allows 2″ to 3″ of the edging (for 7″ edging” to project above the surface when placed on top of the bed. However you can adjust the depth of the trench to modify this.

For 2 x 7 edging, dig a trench about 8 inches wide. Adjust the depth so that the underlying 2″ to 3″ bed of concrete will expose the desired amount of kerb above the surface.
© Eugene Brennan

Some stumps had to be taken up when digging the trench.
© Eugene Brennan

Step 2: Place a Line the Length of the Trench

A string line acts as a guide for laying stones which are placed so that the back edge of a stone just touches the line along it’s whole length. The line also acts as a height guide. You can make a line with a couple of iron bars, wooden stakes or similar and some string. Tie the string loosely onto each bar so that it can be moved up and down the bars when they’re hammered into the ground, rather than pushing the bars in or out of the ground to adjust height.

1. Push or hammer the first bar into the ground.
2. If the trench is straight, pull the line tight and hammer the bar at the other end of the line into the ground.
3. Adjust the height of the line at each end so that it’s at the height you want your edging stones (2″ to 3″ above the surface). If the ground is sloped, usually you want the edging stones to follow the slope, so don’t level the string.
4. The string will sag along it’s length just like a clothes line or electricity wires. So you need to support it every 6 feet or so with additional bars/pegs. Instead of tying these to the line, just twist the string around each bar. The easiest way to do this is by holding the bar horizontally and wrapping a single turn of string around it. Then twist the bar into a vertical position and push into the ground.
5. By sighting along the entire length of the line, if necessary adjust the position of the bars from front to back of the trench so that they all line up.
6. Again by sighting along the line, adjust string up or down on the intermediate pegs so that the line is straight along the full length and doesn’t dip on any peg.

Keep the line at the same height above the surface on sloping ground. Use intermediate bars every 6 feet or so to stop it sagging
© Eugene Brennan

Twist string around intermediate bars. This is an old stair rod. These were nice and smooth, so I was able to slide the string up and down to get the string straight over the full length of the driveway.
© Eugene Brennan

© Eugene Brennan

© Eugene Brennan

Step 3: Mix the Concrete for Bedding the Edging

Use a C20 general purpose mix which is 1 part cement to 4 parts stone and 2 parts sand. (These proportions are by volume not by weight). A single mix with a small cement mixer will produce about a wheel barrow full of concrete, sufficient to bed three, 3 foot long (approx 1 m) kerbs. Concrete should be mixed stiffly with as little water as possible so that it will support edging stones without being squeezed out from underneath. You can learn how to mix concrete using either of my two guides:

• “Easy Steps to Making Concrete With a Cement Mixer“
• “8 Steps to Mixing Concrete by Hand“

Concrete should be stiff so it doesn’t squeeze out from underneath stones and they don’t sink into it.
© Eugene Brennan

Step 4: Lay a Bed of Concrete

1. Lay enough concrete in the trench to bed two or three stones and extend it just beyond where the last edging stone in this group will be placed. I’ve found a garden spade is the most convenient tool, but you can also use a brick laying trowel. As shown in the diagram below, concrete should extend backwards 2″ to 4″ behind the the line and stones so that it acts as a base for the haunching added later and also extend a couple of inches forward into the trench. The depth of the bed should be about 2″ to 3″ (50 mm to 75 mm).
2. A short piece of timber (e.g. 1 foot of 2 x 7) the same height as an edging stone, is useful for checking the bed is sufficiently deep. Allow 1/2″ to 3/4″ (12 to 18 mm) or so of concrete for sinking/ tapping a kerb into place. Therefore when the top edge of the timber is this distance above the string line, the bed is the correct depth.
3. Smooth off the bed with a piece of timber or trowel to make it roughly level.

Use a shovel, spade or builder’s trowel to lay a bed of concrete for several stones.
© Eugene Brennan

Smooth the bed with a trowel or piece of wood.
© Eugene Brennan

Using a piece of board or similar as a guide, the same height as a stone, check the bed is deep enough so that stones can be hammered down about 1/2 to 3/4″ (12 mm to 16 mm) into it.
© Eugene Brennan

Step 5: Bed the Edging in the Concrete

1. Lower a stone gently into place. If concrete is a bit on the soft side, plonking it into place can result in it sinking too much. Ensure it butts tightly up against stones previously laid. Align it so that the back of the stone lines up with the string line.
2. Using a mallet or the end of the handle of a builder’s hammer, tap evenly along the top surface of the stone to bed it into place so that the rear top edge is barely in contact with the line. This can be a bit tricky to judge with curved top edging stones, so use a level from the front, extending back to the line. The level should barely touch the line when a stone is sufficiently bedded down.
3. If the stone is too low in the concrete bed, lift it back out and add concrete in the low spots. If your mix is too wet, concrete can squeeze out from under a stone, so allow a little extra time for it to stiffen and pull it back into place.
4. Check the vertical face of the stone is plumb using your level and adjust as necessary.
5. If you intend to lay further stones later after concrete has set, smooth and taper the bed of concrete that extends beyond the last stone downwards so that it doesn’t obstruct laying the next stone.

The top of the edging stones should be level with the top of the string. Plumb the vertical face also with a level.
© Eugene Brennan

Extend the bed beyond the end of the last stone you intend to lay so that when you add more bedding concrete, it will merge with it.
© Eugene Brennan

Use a mallet or the handle of a lump hammer to tap stones down into the bed. Don’t use the hammer head itself to avoid chipping or cracking concrete. (Sorry this photo is out of sequence taken after haunching added at the front!)
© Eugene Brennan

Stones should line up with the line.
© Eugene Brennan

Step 6: Add Support at the Front and Back

I found that using blobs of concrete at the front and back at each joint helps to keep stones in place until haunching is placed at the back. A pointing trowel is small and useful for doing this. Press the blobs tightly against the stones to give a buttress effect. Continue to lay stones, adding blobs of concrete at each joint.

Use blobs of concrete back and front of stones at joints to keep them in place pre-haunching.
© Eugene Brennan

© Eugene Brennan

Step 7: Place the Haunching Concrete

• Once concrete is sufficiently stiff, place haunching concrete at the back along the full length of edging. Use a spade, shovel or if the space is narrow, a trowel.
• In general, haunching should extend at least half way up the back of a stone but you can finish it 1″ to 2″ (25 mm to 50 mm) below the top edge. The width of the haunching bed should be at least the width of an edging stone. (For my edging project the stones were 2″ wide, but I made the haunching bed 4″ wide).
• Pack the haunching with a piece of 2 inch board. You can slope it slightly to aid water run off.
• Most pressure will come from the front of a driveway as vehicles push gravel downwards and outwards to the side. So haunching is necessary to prevent edging stones from moving backwards relative to each other. You can also add haunching at the front. I just used three blobs per stone, extending up to about 3″ below the top of a stone and then back filled in front of the stones with a mixture of sand and small gravel. I can’t guarantee this is adequate though, so you can haunch along the full length of stones with concrete to be totally certain they won’t move. Front haunching doesn’t need to extend up the stones as far as at the back, a couple of inches being adequate.

Haunch and bed dimensions
© Eugene Brennan

Bed and Haunching Dimensions

Dimension	Guidance
Haunch height	At least half height of stone minium, but ideally up to 2″ (50 mm) below top edge of stone
Haunch width	At least width of stone, but ideally about 4″ (100 mm)
Bed depth	2″ to 3″ (50 mm to 75 mm)
Bed width	Haunch width + width of stone + 2″ to 3″ (50 mm to 75 mm) in front of stone

Use a trowel to place concrete at the back of edging.
© Eugene Brennan

Pack the concrete with a short length of board.
© Eugene Brennan

© Eugene Brennan

Finished result. A couple of the stones at the far end were a bit off line vertically, but this was my first time doing this. The last stone in the foreground slopes downward at a gap in the row of shrubs.
© Eugene Brennan

Can I Use a Laser as a Guide When Laying Edging?

You can of course. Auto-leveling lasers are available, but not all of them allow you to set them up so that they can shine a beam off the horizontal on a slope. You can use a non-leveling laser and adjust it so that the beam is sloped. Many cheap lasers have beams that aren’t visible outdoors, so this is something you need to check when buying.

In Retrospect

My kerbs are 2″ above the level of my drive. In retrospect maybe I should have raised them an inch or so higher to prevent soil in the raised flower beds from spreading over them if there’s any movement over time or I get a new layer of gravel for the driveway.

Disclaimer 

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualised advice from a qualified professional.

© 2020 Eugene Brennan

8 Types of Wall Anchors and Fixings: Which Should You Use?

© Eugene Brennan

How to Mount Shelves, Cabinets, and More

Fixing stuff to walls is relatively easy, in fact I’ve been doing it since I was 13! My home-made wall plugs made from branches weren’t such a good idea though, and my first shelves fell of the wall when the plugs dried out! In fact, the method used to mount cabinets, brackets for shelves, coat hooks, etc., on a wall depends on the nature of the wall construction. In this guide, I cover some the various fixings available to attach items to different types of wall material, including timber studs, plasterboard (drywall) and masonry walls.

Various fixings are used depending on the structure of the surface you’ll be mounting on. If you’re fixing to timber or wooden studs under drywall, you just use screws, but for drywall itself or masonry, the fixing either holds onto the back of the drywall, or expands in the hole respectively. These are the fixings you’ll typically use:

1. Self-drive anchors
2. Spring toggle anchors
3. Hollow expansion anchors
4. Wall plugs
5. Expansion bolts
6. Frame fixings
7. Express nail anchors
8. Philips head screws

Note: The name for the device used to attach items to walls differs between countries. In the US, the term “anchor” is more common, whereas in the UK, the term “fixing” is used. Also what’s called “plasterboard” in the UK is referred to as “drywall” in the US.

“Fixing” is the British term for “anchor” (US).

“Drywall” is the American term for “plasterboard” (UK).

Precautions When Drilling and Fixing to Walls

• Determine whether there are any services (electric or signal cables or water, gas or waste pipes) in the walls before drilling. Ideally turn off power if possible. A detector will help to locate some services.
• Use a sufficiently short drill so that you don’t drill through to the other side.
• Use a mask when drilling to protect yourself from sawdust or cement dust.

What Tools Are Needed for Fixing to Walls?

• Pencil or marker
• Drill for drilling holes
• Screwdriver or cordless drill/driver
• Spirit level or a good eye!
• Drill bits

If you are buying a stud detector, get one which detects metal.

Mounting to Stud Walls

Light items, such as small picture frames, wall clocks etc., can be screwed directly to timber panelling/boards if you don’t have drywall.

For items carrying heavy loads, a more secure method is to drive screws into the center of the wall studs. Heavier items such as cabinets and TV brackets need to be fixed to the wall studs with 10 or 11 gage (about 5mm diameter) screws. Modern LED TVs are quite light compared to CRT or plasma types, so you may get away with mounting the brackets directly onto boards or drywall.

How to Find Studs

Plasterboard (drywall) is nailed onto a hollow timber framework known as a stud wall or framing, built from 2 x 4s. (2 inch x 4 inch cross section timbers) or larger cross sectional area (CSA) timber. This is composed of vertical and horizontal sections called studs and noggings (blocking) respectively.

Studs are typically spaced 16″ (400mm) apart and can be found with an electronic stud detector or identifying where drywall sheets butt together at the centre of a stud. You can find a stud by tapping the wall and when you locate a point where the sound is less “hollow,” a stud is underneath.

If you are buying a stud detector, get one which detects metal (useful for finding plumbing and other services in the wall and/or power cables).

Mounting and Screwing to Stud Walls

Once you have found a stud, mark its center, and screw your fixture onto the wall with wood screws. Plasterboard is generally 13 mm (1/2 inch) to 16 mm (5/8 inch) thick, so make sure you size the length of screws appropriately. i.e. allow for the thickness of the plasterboard and the fixture, with 40 mm (1 1/2 inch) of screw thread actually screwing into the stud.

Metal shelf brackets usually have pre-drilled holes. Cabinets sometimes have flat pieces of metal at the back from which the cabinet can be screwed to the wall and “suspended”. If the back of a cabinet is fairly thick and not just thin hardboard, you can drive screws straight through from front to back and into the wall. If the back of a cabinet isn’t pre-drilled, drill holes the same diameter as the screws you are using and then screw the screws into the wall. Choose the length of the screw to cater for the combined thickness of the back of the cabinet and drywall.

Stud Wall
Ahp378, Creative Commons Attribution-Share Alike 3.0 Unported via Wikimedia Commons

Fixings for Mounting to Plasterboard (Drywall)

For mounting to studs and plasterboard (also known as drywall), there are several options. You can use plastic wall plugs (see mounting on masonry walls below) directly pushed into the plaster. However, these are only suitable for very light loads (e.g., small mirrors, light picture frames and smoke alarms). The appropriate fixings for drywall are metal or plastic self-drive fixings (anchors), spring toggle anchors or hollow expansion anchors. For heavier loads, screw directly into the wall studs.

1. Self-Drive Anchors

These are small metal or plastic fixings with a coarse outer thread and inner thread which takes a screw. These will either have a cutting edge and make their own hole in the plasterboard/drywall or you may have to drill a small pilot hole first. The pilot hole diameter may be marked on the fixing, but if not, drill a hole the diameter of the unthreaded core of the fixing in the plasterboard. Now drive the fixing into the plasterboard either using a special dedicated drive bit for a cordless drill or a normal screwdriver. Then attach whatever you are hanging on the the wall to the fixing using the screw provided. These are fine for mounting socket outlets, switches, light fittings on ceilings and other light loads.

Self-drive drywall anchors and drive bit for cordless drill. Metal versions are also available. The pilot hole size which needs to be drilled in the plasterboard (6mm), is marked on the fixing
Smial, Free Art Licence via Wikimedia Commons

2. Spring Toggle Anchors

Alternatively, you can use spring toggle fixings. You drill a hole for these, insert the fitting into the hole and two spring loaded arms open out at the back of the drywall giving anchorage. These provide better anchorage than self-drive anchors which could pull out of the drywall if the load is heavy. The disadvantage of these is that if the screw is removed, the toggle will fall down inside the wall. They also require a relatively large hole drilled in the drywall.

Spring toggle anchors
Tenbergen, Creative Commons Attribution-Share Alike 3.0 Unported via Wikimedia Commons

3. Hollow Expansion Anchors

The hollow shell of these anchors expands as the screw is tightened, pushing against the back surface of the drywall. This gives good grip and the fixings are suitable for heavier loads such as TV brackets. They are available in plastic or metal versions.

Hollow expansion anchors
Dmitry G, Creative Commons Attribution-Share Alike 3.0 Unported via Wikimedia Commons

Hollow expansion anchor.

Fixings for Mounting to Masonry Walls

Masonry includes concrete blocks, bricks, solid concrete wall, stone and aerated concrete blocks. Typical fixings include:

• wall plugs
• expansion bolts
• frame fixings
• express anchors
• Philips head screws

Tools Required

1. Cordless or corded, hammer action, power drill
2. Masonry drill bit. A 1/4 inch (6mm) bit for drilling the holes and 6 mm wall plugs are ideal for mounting light shelf brackets, socket and switch outlets, etc. Use an 5/16 (8mm) bit and wall plugs for heavier loads (cupboards, bookshelves etc).

Drilling Holes and Mounting

• Before drilling a wall make sure you know where cables and pipes are routed. You can buy a voltage detector for detecting the presence of power cables.

4. Wall Plugs

If a wall is solid construction you must use plastic screw anchors also known as wall plugs. These expand and grip the side of the hole when a screw is driven into them.

The hole is drilled to adequate depth, the wall plug inserted and the fixture screwed onto the wall with 8 or 10 gage (4mm or 5mm) diameter screws. 40 to 50 mm (1 1/2 to 2 inch) long screws are fine for most applications. Use thicker wall plugs and screws for heavier loads.

Typical wall plug/anchors for masonry walls. The required drill bit size in mm is indicated on the shank
Bronzaclose, Creative Commons CC0 1.0 Universal Public Domain Dedication via Wikimedia Commons

To attach a bracket to a wall, first position it against the wall and mark the first hole with a pencil or nail. Don’t mark all the holes because if the drilled hole goes off course, or is a little to one side, the other holes will be out of alignment. Drill the hole with a suitable diameter masonry drill bit, rake or vacuum out the dust and insert the anchor into the hole. Place the bracket against the wall again and line up the center of the anchor in the wall with the hole in the bracket. Mark the next hole and drill it. Repeat for all the holes and finally attach the bracket with wood screws.

If you’re mounting shelf brackets, hold the second bracket against the wall and either rest the shelf on the two brackets and level with a spirit level or if the span is short you can just rest the level on the two brackets without the shelf. Mark the top hole in the second bracket, drill the hole for the screw fitting and then mark and drill the remaining holes as described above. Finally, screw the bracket to the wall.

To use wall plugs (rawplugs), drill the recommended size hole with a hammer action power drill and masonry drill bit and use the proper screw size. The fixing expands as the screw is driven home and grips the side of the hole. People sometimes generically refer to wall plugs as “Rawlplugs” because the wall plug was invented by John Joseph Rawlings, the founder of the Rawlplug company.
Wall plugs normally have the drill diameter marked on them and possibly also the max diameter screw that can be used.

Screw sizes and the bit size for the hole are sometimes marked on the wall plugs.
© Eugene Brennan

Masonry drill bit
Emrys2, Creative Commons Attribution-Share Alike 3.0 Unported via Wikimedia Commons

Drilling Concrete for Wall Plugs

5. Expansion Bolts

If you need to mount heavy loads on masonry walls, there are a couple of options. You can use expansion bolts (wedge anchors) and these are available in a variety of configurations. The most basic type shown in the photos below has a bolt which screws into an outer sleeve. A suitably sized hole is drilled in a wall (the diameter is usually printed on the anchor) and the expansion part of the fixing is inserted in the hole. The bolt is passed through the fixture being attached to the wall and the bolt tightened with a wrench. The fixing expands and securely grips the side of the hole. You can get these fixings with a hook or eye at the end for attaching cables and ropes etc (e.g., a clothes line). Another type has a nut rather than a bolt head at the end.

Important! Expansion fittings shouldn’t be excessively tightened to avoid cracking concrete. They should also be kept in a minimum distance from the edge of concrete or solid blocks. A crack in this case could cause a section to break off and the bolt to lose its grip on the masonry.

Expansion bolt (Wedge anchor)
© Eugene Brennan

When the bolt is tightened, the sleeve expands and grips the side of the hole
© Eugene Brennan

6. Frame Fixings

For fixing timber frames to concrete or brick walls, you have two options: frame fixings or express anchors.

Lengths of timber, stud walls or any other type of thick material can be fixed to masonry with frame fixings. These are like a long wall plug. An 8mm to 10mm hole is first drilled through timber and masonry behind it and the fixing tapped home until the edge is flush with the timber. Then the screw is either screwed or hammered into the plastic sleeve. You can also use these fixings for attaching things to masonry walls, after the walls have been insulated with composite drywall/insulation boards, e.g., radiators. Choose an appropriate length so that the part of the fixing that expands is within the masonry.

Frame fixing

7. Express Anchors

Express anchors represent another option for attaching timber beams, fence posts, door frames etc to walls. These fixings are hollow with a slot in the side and slightly larger than the hole which is drilled for them. When hammered into a hole, they squeeze tight and wedge firmly into position. They can also be used for joining timber as they provide the advantage of a screw, resisting being pulled out, and the convenience of a nail. The disadvantage of course is that unlike a frame fixing, they are permanent and can’t be easily removed.

Note! Neither frame fixings nor express anchors are recommended for fixing into cavity blocks. In any case, they should be at least 4 inches (100mm) in from the edges of blocks and spaced no closer than 4 inches to prevent cracking of the masonry.

Express nail anchor
© Eugene Brennan

Express anchors can be used for attaching timbers to walls
© Eugene Brennan

8. Philips Head Screws

For brick or stud walls, I generally use Spax wood screws or similar. These type of screws have a tip which drills through timber as the screw is driven, making for easier driving. A Philips head allows you to drive the screw with a cordless drill.

Spax wood screws
© Eugene Brennan

Frequently Asked Questions

What screws should I use for brick or stud walls?

Spax wood screws or similar with a Philips head have a special tip that makes drilling easier.

What are the strongest drywall anchors?

Spring toggle anchors provide the most anchorage when it comes to drywall/plasterboard.

What kinds of anchors can hold a TV?

Hollow expansion anchors are suitable for heavy loads, such as TVs.

How do I mount heavy items on walls?

Heavy items should be mounted to a stud, if possible. If you are not mounting on a stud, use a toggle anchor. The size of the toggle depends on the weight of the piece and the thickness of the wall. If you are mounting a heavy item on a masonry wall, use an expansion bolt (anchor wedge).

How much weight can a toggle anchor hold?

The thicker the anchor, the more weight it can hold. A thick toggle anchor can hold up to 50 pounds. Hollow expansion anchors can hold up to 100 pounds.

Disclaimer 

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

Power and hand tools can be dangerous. Read and understand all manuals before use and take reasonable precautions including wearing personal protection equipment (PPE) to prevent against injury. 

© 2011 Eugene Brennan

lucille12 on April 05, 2015:

The right hangers can certainly help in organizing your home and eliminating the piles that lay around the home.

How to Build a Low-Maintenance Garden Storage Shed From Steel Cladding

© Eugene Brennan

The epic saga of the two year construction of a garden shed…

Have you ever wanted to build your own garden shed? I always have and attempted my first one when I was about 10 years old, but abandoned the project because of lack of materials, skills and tools! Eventually, 40 years later, I got around to building a proper garden tool shed.

How to Use a String Trimmer Properly Without Breaking the Line!

Petrol and electric corded trimmers
© Eugene Brennan

This garden power tool has many names depending on where you live in the world, but one thing is sure — it certainly beats a hedge shears for trimming and edging! Like most power tools nowadays, string trimmers are available in petrol, electric corded and rechargeable battery cordless versions.

How to Change Lawn Mower Oil: No Fancy Tools Needed!

© Eugene Brennan

Motor oil is an essential requirement of all engines. It has several functions, including lubrication of metal parts in contact (reducing friction), cooling, keeping surfaces clean, sealing and corrosion inhibition.

How to Replace a Spigot Washer – Dripping Outside Tap (Bibcock)

© Eugene Brennan

Like any other faucet (also known as a tap), a spigot has an internal washer which seals and cuts off flow when the spigot is turned off. Eventually after thousands of on/off cycles, this washer wears away, and the result is a dripping spigot.

A Guide to Names of Weeds (With Pictures)

AI image generated by Bing Image Creator

Weed Identification Guide

This guide helps you identify the 25 most common weeds that you’ll encounter in your yard, flower beds or lawn. Some are annuals and others are perennials—many are easy to eradicate, others more difficult to eliminate.

How to Build a Nest Box for Robins From Scrap Timber

© Eugene Brennan

In this guide I’m going to make a nesting box suitable for European robins, although it can be sized down a little to make it suitable for finches, wrens or similar small songbirds. You can make a birdhouse like this from any waste timber (lumber) that comes to hand such as cladding, fascia or soffit, skirting board (baseboard), palette timber or ply.

A Complete Guide to Pipe Fittings and How to Use Them to Connect PEX, PVC and Copper Tube

© Eugene Brennan

A DIY Guide to Plumbing fittings and Pipe Materials

Basic plumbing isn’t rocket science. If you are reasonably adept at DIY, understand the basics, and take care when putting it all together, it’s not too difficult. This is a comprehensive and easy-to-understand guide to pipe types, plumbing fittings, thread sizes, with instructions for how to use fittings to connect copper, PVC, and PEX pipes.

How to Mix Concrete With a Cement Mixer: Steps and Tips

Learn how to use a concrete mixer to get consistent, high-quality results every time.
Original image, pre-text overlay, Antranias, public domain via Pixabay.com.

Mixing Concrete With a Mixer

In my other guide on mixing concrete by hand, we discovered that it’s feasible to mix concrete with just a shovel. This is fine for small amounts of concrete. However, a mixer thoroughly mixes the materials, lessening the chances of weak spots in the final result. If you’re going to be laying floors or pavements or casting gate pillars or walls, a cement mixer is pretty much essential if you want to get the job done reasonably quickly.

What Is Concrete and What Are the Different Strength Mixes?

I go into more detail in my other article, but let’s cover the basics here:

• Concrete is a composite material consisting of cement, sand and stone.
• Cement acts as a binder joining the stone and sand together.
• Stone and sand, also known as aggregate, mixed together on their own with no cement added would have no strength. However, cement holds them together and interlocks the particles like a 3D jigsaw puzzle. This is what gives concrete its shear and compressive strength.

Concrete Mixes

Varying the proportion of cement, sand, and stone controls the strength of concrete and the force it can withstand without failing. “C” types are used to specify the strength of concrete. These recipes specify the proportion of materials (by volume) which will produce concrete that can have a certain strength.

• C20 is a general-purpose mix for fixing posts, making concrete pads, doorsteps, and bases for garden sheds, floors, etc. This mix consists of 1 part cement, 4 parts stone and 2 parts sand.
• C30 is a stronger mix suitable for thinner and narrower concrete slabs, e.g. pavements. This mix consists of 1 part cement, 3 parts stone and 2 parts sand.

Quantity of Water Needed When Mixing Concrete

The drier concrete is, the stronger it is. Ideally, it must only be wet enough so that it’s workable.

By Weight of Cement

The quantity of water needed should be 0.4 to 0.6 times the weight of cement. For a 25kg (4 stone approx) bag, if we take a figure of 0.5, this works out at:

25 x 0.50 = 12.5 kg of water

Now since 1 kg of water has a volume of 1 litre, this equates to 12.5 litres of water for 25 kg of cement.

12.5 litres is nearly 2 3/4 imperial (UK) gallons or 3.3 US gallons.

In Terms of Buckets

Loose cement has a density of about 1.5 kg/litre. That’s 1.5 times the density of water. So if we have 1 bucket of cement, it takes 1.5 buckets of water to weigh the same amount, and again, taking a figure of 0.5, we need 0.5 x 1.5 = 0.75 or 3/4 buckets of water per bucket of cement.

Concrete shouldn’t be excessively wet after mixing and should have a minimum slump. A shovelful deposited on the ground should self-support itself without spreading out (slumping). Concrete that is too dry is unworkable and also won’t have sufficient water for the chemical reaction with cement to progress properly and the concrete to cure, therefore reducing its ultimate strength.

Too much water is also detrimental to the final strength because as excess water that doesn’t combine with cement evaporates, it leaves behind micropores which are tiny air cavities. The concrete is effectively a sponge.

Tools Required for Mixing Concrete in a Mixer

• Cement mixer: Electric or gas (petrol)
• 3 buckets: One for cement, one for sand and gravel and one for water (aggregate can be wet, so having a separate bucket for cement keeps the bucket dry, otherwise cement will stick to the sides when measuring it out)
• Barrel: For holding water
• Wheelbarrow: For transporting concrete
• Shovel

A barrel is more convenient than a hose because buckets can be filled quicker.
© Eugene Brennan

Stone and sand can be wet, so using a separate bucket for cement keeps it dry and stops cement sticking to the sides.
© Eugene Brennan

PPE for Mixing Concrete

• Dust mask to protect your lungs
• Gloves to protect your hands from abrasion and cement which is an irritant and somewhat caustic
• Safety glasses to protect your eyes from splashes from the mixer
• Steel toe cap shoes/boots for foot protection

Warning

Always read the safety information on bags of cement.

How to Use a Cement Mixer: Step-by-Step Guide

A cement mixer allows you to mix concrete quickly, and you can produce a wheelbarrow of it in about 10 minutes. Here are some tips to get the best results.

1. A UK builders bucket will typically hold 3 UK gallons or 13.5 litres. These are convenient for measuring out quantities of materials before mixing commences.
2. A small Belle mixer such as the Minimix 130 or Minimix 150 will mix about 90 litres of concrete, so if you do a C20 mix, i.e. 1 bucket of cement, 2 buckets of sand and 4 buckets of stone, this will produce about a wheelbarrow full of concrete. You can make the mix stronger by reducing the amount of stone to 3 buckets (C30 mix).
3. Measure out the stone, sand and cement into 3 separate piles on the ground. A sheet of plastic or large wooden board, such as a sheet of plywood, keeps the ground clean and prevents contamination of the materials by soil and dirt.
4. It’s advisable to use a small barrel or other type of large container to hold water if you’re doing several mixes. You’ll need multiple buckets of water, and you don’t want to have to go off filling a bucket from a tap/faucet or hose if a mix begins to stick to the drum.
5. Start the mixer.
6. Shovel half of the stone in first and one-quarter of a bucket of water. The abrasive nature of stone helps to scour any remaining wet concrete stuck to the drum from an earlier mix session.
7. Next, add cement, sand and stone alternately from the piles. As you add cement and sand, watch for a moment to see how the mix is progressing and add water so that the mix is not over-sloppy but at the same time not so dry that it sticks to the drum.
8. You can add all the materials to the drum first and do a dry mix. However, cement will stick to the inside of the drum, and the likelihood is that material at the back of the drum won’t mix properly and get wetted as you add water. So it’s better to add them a bit at a time.
9. Continue to add the remainder of the cement and sand.
10. Never put a shovel into a rotating mixer drum. The mixing spoons can catch the shovel and swing it around, and hit you in the face. If the mixture seems to be sticking to the back of the drum, stop the mixer, scrape the mix off the back and pull it forward. Repeat this, or add a little more water as necessary.
11. If the mix starts to overflow out of the drum, place the wheelbarrow underneath to catch any spill.
12. Allow to mix on full speed for about 3 minutes.
13. Reduce the speed of the engine and commence unloading the mixer into the barrow.
14. When the drum is empty, a new mix can be started. Add some water first to rinse off the concrete stuck to the inside of the drum. This slush can be incorporated into the next mix. If you are working alone, stop the mixer so that you can deal with transporting and unloading the barrow.
15. Don’t forget to wash all concrete from your tools before it sets and hose out the drum, ideally while the engine is running and the drum is tipped. Try to avoid getting water from the hose onto the engine. If the mixer is electric, unplug it and relocate the extension lead out of range while hosing.

Protecting Concrete in Dry and Cold Weather

Water added to concrete isn’t just for making it plastic and workable so it can be formed into slabs and other shapes. Water or H₂O combines with cement in a chemical reaction and actually becomes part of the concrete for all eternity (well not quite, but as long as the concrete is in existence!).

Any excess water evaporates over a period of weeks. Since water is necessary for this chemical reaction, it’s essential that it is retained until concrete cures or hardens over days to weeks. So once you lay concrete, cover it with plastic to stop it from drying. This is important in hot weather and/or when windy. Water can be added onto the surface in subsequent days to keep it wet while curing.

Protecting Concrete in Cold Weather

Cold weather is defined as when the average temperature is less than 41 F (5 C) and also less than 50 F (10 C) for 12 hours in a 24-hour period. During cold weather, concrete should be protected with blankets, bubble wrap or other suitable insulation. This traps the heat of the chemical reaction and stops the concrete from freezing.

Concrete is a cheap, strong material that can be used for making lots of things like gate pillars and pavements.
© Eugene Brennan - From the Article "How to Build a Concrete Gate Pier"

A newly concreted slab at the back of my house.
© Eugene Brennan

How Do I Store Cement?

Cement bags should be kept up off the ground so moisture doesn’t soak into them. You can use a palette or place the bags on boards spanned between wood offcuts or bricks. Unused, unopened bags of cement can be sealed into plastic bags (use heavy rubble bags instead of trash bags, which can puncture) to lengthen its shelf life, but apparently, it still deteriorates if bags are airtight. It’s recommended that it should be used within 6 months.

How Long Does Cement Last? Does It Have a “Use By” Date?

Use cement within three months of the manufacture date printed on the bag. After this it often becomes lumpy where it’s in contact with the inside of the bag.

Disclaimer

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters. 

Power and hand tools can be dangerous. Read and understand all manuals before use and take reasonable precautions including wearing personal protection equipment (PPE) to prevent against injury. 

© 2020 Eugene Brennan