Woodworking & basic carpentry

Sawing square

One of the most useful – and easiest to make – aids to sawing is a bench hook. It’ll help you to grip the wood you want to cut, and to protect the surface on which you are working. You can make one up quite easily, by gluing and screwing together pieces of scrap timber. You also need the ability to control the saw, and there are three tips that will help you here. Always point your index finger along the saw blade to stop it flapping from side to side as you work. And always stand in such a way that you are comfortable, well balanced, and can get your head directly above the saw so you can see what you are cutting. You should also turn slightly sideways on.

This stops your elbow brushing against your body as you draw the saw back – a fault that is often the reason for sawing wavy lines. Starting the cut Position the piece of wood to be cut on the bench hook and hold it firmly against the block furthest from you. Start the cut by drawing the saw backwards two or three times over the far edge to create a notch, steadying the blade by ‘cocking’ the thumb of your left hand. Make sure that you position the saw so that the whole of this notch is on the waste side of the line.

You can now begin to saw properly using your arm with sort of piston action, but keep your left (or right as the case may be) hand away from the saw. As the cut deepens gradually reduce the angle of the saw until it is horizontal. At this point you can continue sawing through until you start cutting into the bench hook. Alternatively, you may find it easier to angle the saw towards you and make a sloping cut down the edge nearest to you. With that done, you can saw through the remaining waste holding the saw horizontally, using the two angled cuts to keep the saw on course. Whichever method you choose, don’t try to force the saw through the wood – if that seems necessary, then the saw is probably blunt. Save your muscle power for the forward stroke – but concentrate mainly on sawing accurately to your marked line.

Cleaning up cut ends

Once you have cut the wood to length, clean up the end with glasspaper. A good tip is to lay the abrasive flat on a table and work the end of the wood over it with a series of circular strokes, making sure that you keep the wood vertical so you don’t sand the end out of square. If the piece of wood is too unmanageable, wrap the glasspaper round a square piece of scrap wood instead and sand the end of the wood by moving the block to and from – it’ll help in keeping the end square.

Simple joints in woodwork and joinery

It’s often thought that only elaborate joints give good results in woodwork. It isn’t true. There are simple ways to join timber, and one of the simplest is the butt joint. It’s easy to make, can be used on natural timber or man-made boards, and it’s neat. What’s more, given the right adhesive and the right reinforcement, a butt joint can also be strong enough for most purposes.

The great thing about butt joints is their simplicity. You can use them on any kind of timber or man-made board, provided it isn’t too thin – not under 6mm. The only problem you will run into is where you are joining chipboard. A special technique is needed here to get the screws to grip. Although it is possible to simply glue two pieces of wood together, unless you add some kind of reinforcement the result won’t be very strong. So in most cases, the joint should be strengthened with either screws or nails.

The question is which? As a rule of thumb, screws will give you a stronger joint than nails. The exception is where you are screwing into the endgrain of natural timber. The screwthread chews up the timber to such an extent that it has almost no fixing value at all. Nails in this case are a much better bet.

Choosing the right adhesive for carpentry

Even if you are screwing or nailing the joint together, it ought to be glued as well. London Carpenters Robuild use PVA woodworking adhesive, as it will do the trick in most jobs, providing a strong and easily achieved fixing. This type of adhesive will not, however, stand up well to either extreme heat or to moisture; the sort of conditions you’ll meet outdoors, or in a kitchen, for example. A urea formaldehyde is the glue to use in this sort of situation.

Choosing the right joint

There are no hard and fast rules about choosing the best joint for a particular job. It’s really just a case of finding a joint that is neat enough for what you’re making, and strong enough not to fall apart the first time it is used. And as far as strength is concerned, the various kinds of butt joint work equally well.

Marking timber

Butt joints are the simplest of all joints – there’s no complicated chiselling or marking out to worry about – but if the joint is to be both strong and neat you do need to be able to saw wood to length leaving the end perfectly square.

The first important thing here is the accuracy of your marking out. Examine the piece of wood you want to cut and choose a side and an edge that are particularly flat and smooth. They’re called the face edge and face side. Next, measure up and press the point of a sharp knife into the face side where you intend to make the cut.

Slide a try-square up to the knife, making sure that its stock – the handle – is pressed firmly against the face edge. Then use the knife to score a line across the surface of the timber. Carry this line round all four sides of the wood, always making sure that the try-square’s stock is held against either the face edge or the face side.

If you wish, you can run over the knife line with a pencil to make it easier to see – it’s best to sharpen the lead into a chisel shape. Why not use a pencil for marking out in the first place? There are two reasons. The first is that a knife gives a thinner and therefore more accurate line than even the sharpest pencil. The second is that the knife will cut through the surface layer of the wood, helping the saw to leave a clean, sharp edge.

Loft Insulation

Lofts are usually dark, dirty places, so it’s advisable to wear some really old clothes, preferably ones you can throw away afterwards. Blanket insulation, especially glass fibre, can cause irritation to the skin, so you must wear rubber gloves when handling it.

It is also sensible to wear a simple mask to cover your nose and mouth as the insulation material is not only unpleasant but dangerous to inhale. Loose-fill is a dusty material and you’d be wise to wear a pair of protective goggles — as well as a mask-when laying this. You can buy a mask, with replacement lint filters, and the goggles, all of which are available from most DIY stores. You’ll need a good light to work by; a fixed loft light is best, but if there isn’t one, you could rig up an inspection lamp or even a table lamp.

Don’t, however, use a torch: you’ll have enough to contend with without having to carry and aim a light. Don’t use a naked flame because the risk of fire is high in the enclosed space of the loft. Be careful where you tread. The space between the joists-the ceiling of the floor below – is only plasterboard or, in older houses, lath and plaster, and neither will support your weight. Rather than balancing on the joists – especially when you’re carrying rolls or bags of insulation – it’s better to have a short plank or piece of chipboard to stand on, but make sure that both ends are resting on a joist without overlapping, or it could tip up under your weight, with disastrous consequences.

Before you start to lay the insulation you should remove any boxes or other items you have stored in the loft to give you plenty of room to manoeuvre: if there’s too much to take down from the loft you can shift it up to one end of the loft, lay the insulation in the free area, then move the boxes back again and lay the other half. Clean up the spaces between the joists using a vacuum cleaner with a nozzle attachment to enable you to reach awkward corners. If you don’t have one you can use a soft bristled broom or a hand-brush and a dust-pan, but you’ll stir up a lot of dust in the process. Use small pieces of the insulation material to block up any holes made in the ceiling for pipework to and from storage tanks.

Laying the insulation

Laying the blanket type of insulation is simplicity itself: all you do is to start at the eaves and unroll the blanket between the joists. On widely-spaced joists it’ll just lie flat on the loft floor but if the joist spacing is narrow, or irregular, you can tuck it down and allow it to curve up the sides of the joists. Cut or tear small pieces of blanket from the roll to fit very small nooks and crannies.

Butt up new rolls and allow for extra material at beams and pipes that are set at right angles to the joists. Cut the insulation and tuck it under the obstruction, then butt up the next piece to it. Don’t insulate under the cold water tank, which will be mounted on timber bearers at right angles to the joists: heat rising through the ceiling immediately beneath the tank will help to prevent the water freezing in very cold weather. The tank itself should be insulated, with glass fibre blanket or expanded polystyrene sheets all round and on top, or you can use a proprietary tank lagging kit, available from DIY stores.

If your tank is mounted high above the loft floor — usually to enable you to get a sufficient head of water for a shower unit – you can insulate underneath it. The whole tank should, in this case, be lagged. Cut a square of blanket to cover the top of the loft hatch cover and tack it in place, leaving an overlap to stop draughts getting into the loft space. If you’re laying one of the loose-fill materials you’ll have to stop it from falling into the wall cavity at the eaves. Place a few bricks on edge, or a panel of chipboard, between the joists near the eaves, to contain the granules. Empty out the bags between the joists, starting at the eaves, and use a specially shaped timber spreader (see Ready Reference) to spread it to the correct thickness. The loft space will be much colder after you’ve insulated it, so it’s particularly important that you lag any water pipes that pass through the loft

TYPES OF ROOF INSULATION

There are three types of loft insulation you can lay yourself:

• blanket insulation consists of rolls of glass or mineral fibre matting, 80 or 100mm (3 or 4in) thick by about 6 or 8m (20 or 26ft) long. It’s unrolled between the joists

• loose-fill insulation can be a granulated mineral called vermiculite, expanded polystyrene granules, mineral wool fibre or cellulose fibre, available in bags. It’s tipped between the joists and spread out to an even thickness -100mm (4in) forfibre types, 125mm (5in) for granular materials

• sheet insulation is either expanded polystyrene between the joists or rafters, or fibreboard, which is laid across the joists with loose-fill or blanket insulation underneath.

LEVELLING GRANULAR INSULATION To lay granular materials to the correct depth -100mm (4in) – make a timber ‘spreader’ from anoffcut of chipboard, which you draw along the joists. Ensure:
• the body of the spreader just fits between the joists
• the arms rest on the joists • the depth of the body is 100mm (4in) above the loft floor. If your joists are only 100mm (4in)deep, lay the material flush with the top of the joists.

HOW MUCH INSULATION
To work out how many rolls of blanket insulation you’ll need: • multiply the length by the width of the loft to get the number of square metres
• allow a little extra for insulating tanks and pipework.

Insulating the roof

About a quarter of the heat lost from an uninsulated house goes through the roof, and so some kind of roof insulation should be your first priority for saving money on heating bills.

Houses leak heat like a sieve. Up to 75 per cent of the warmth generated within the house finds its way to the outside world through the roof, walls, windows and doors, and this represents an enormous waste of energy and money. Insulation reduces the rate at which heat passes through the various parts of your house’s structure, by trapping ‘still’ air within the insulating material itself.

Still air doesn’t conduct heat much and so wrapping your house in suitable insulation serves the same purpose as putting a tea-cosy on a tea pot: the tea stays hot for far longer. The converse is true during the summer: the insulation bars the heat of the sun. About a quarter of all the heat lost from an average house goes through the roof, and this is a particularly easy area to insulate effectively. What you do is to put your insulation in one of three places: on the highest ceiling; on the loft floor; or on the inside of the roof itself. Insulating the loft floor is the simplest and most effective of these: you should insulate the ceiling where there’s no loft or the roof slope where the loft space has been converted into living accommodation.

Why you should insulate

The savings you can make by insulating your loft depend on whether there’s any insulation there already (it’s the first layer that’s most effective), how much you put in, and whether you can control or alter your heating system to take advantage of the insulation. The last point is particularly important: if you install loft insulation and leave central heating controls as they are with a thermostat in, say, the living room, the most noticeable effect will be warmer rooms upstairs rather than dramatically decreased fuel bills. If, however, you can lower the tempertures in upstairs rooms, or keep them the same as before, by fitting thermostatic radiator valves or by turning radiators down (or off), your house will lose less heat and your fuel bills will be lower. Types of insulation There are four main types of loft insulation you can use: blanket, loose-fill, sheet and blown fibre.

You can install any of the first three yourself but blown fibre must be installed by a roofing contractor. The most extensively used loft insulation material is rolls of glass fibre or mineral fibre blanket, which you lay between the joists of the loft floor. You can choose from either of two thicknesses: 80mm (just over 3 in) and 100mm (4in).

Although you’ll benefit in terms of warmer rooms by installing thicker insulation, the more you put in, the less cost effective it becomes. From a practical point of view thicknesses greater than 125mm (5in) will probably take the insulation over the top of the joists, making walking about or storing things in the loft rather difficult. To save storage and transportation space the material is compressed when rolled up and packaged but it regains its original thickness quite quickly when unwrapped. The most common width of roll is 400mm (16in). Lengths vary from brand to brand, but they’re usually about 6 to 8m (20 to 25ft) long. Some glass fibre insulation is available in 600mm (2ft) wide rolls for use in lofts with wider-than-usual joist spacings.

The 400mm (16in) width is the most suitable size for most houses and allows a little to turn up where it meets the joists. Joists are usually 400mm (16in) apart but they might be as much as 450mm (18in) or as little as 300mm (1ft). If you have narrow-spaced joists the 600mm (2ft) width is probably the best to use: you can cut a roll in half with a panel saw while it’s still in its wrapper. Working out how much insulation you’ll need is simply a matter of multiplying the length of the loft floor by the width to calculate how many square metres there are.

Blocked roofing gutters

Blocked gutters

Roof rainwater gutters may become by leaves or other objects. An overflowing gutter isn’t an instant catastrophe but, if neglected, it will cause dampness to the house walls. An inspection, removal of debris and a hose down of gutters should be a routine part of every householder’s maintenance of the roof and property. Roofers London Robuild

Fixing new roof guttering

The obvious first step is to assemble the various bits and pieces you need, and you can use the old guttering system as a model to decide what’s required. It’s best to measure up the length of the guttering itself, allowing a little extra to be safe.

At the end of the run furthest from the downpipe, fix a gutter support bracket as high up the fascia as possible, and about 150mm (6in) from the end. The fixings here, and elsewhere, are made with 25mm (1 in) screws. Choose ones that are galvanised to stop them rusting.

Insert a nail into the fascia board level with the bottom bracket. . At the other end of the run, 150mm from the downpipe, fix another nail, tie a length of string tightly between the two, and use a spirit level to check that this string is level. When it is, lower the second nail by the amount needed to ensure that the guttering runs downhill towards the outlet.

This ‘fall’, as it’s called, varies according to the type of guttering, so check the manufacturer’s recommendations. Usually, it is in the region of 5mm for every metre of gutter run. Once you’ve found the right line for the gutter, fix another bracket level with the lowest nail. The next job is to fix the next bracket 1m (39in) from the one at the downpipe end of the run, using the string as a guide to set it at the correct level. Use these two brackets to support a length of gutter with the downpipe outlet attached.

Exactly how you join the gutter to the outlet – or indeed make any other joins in the guttering – will vary from brand to brand. With some, you slip the ends of the components into a special jointing piece called a union, and clip the whole lot together. With others, one of the components will have a union built into its end. Now work your way along, building up the gutter run as you go and adding additional support brackets as required, again using the string as a guide.

In most cases, you will need a bracket every metre, plus one on each side of every join – though some ranges contain combined unions and support brackets. Check the manufacturer’s recommendations. The only problem you may run into is when you have to cut the guttering to length, either to go round a corner, or to finish the run with a stop end. Do the cutting on the ground using a hacksaw, making sure that you cut the end square. Any roughness left by the saw should be cleaned up with a file.

If you want to turn a corner, fix the corner piece before cutting the straight piece of gutter to length. You can then use it to work out exactly how long the straight gutter length needs to be. When cutting to finish at a stop end, it is usual to leave about 50mm (2in) of gutter projecting beyond the ends of the fascia. When you’ve finished the job and checked to see that all the joints are properly connected, take a bucket of water to the highest point of the gutter and pour it down. If the gutter doesn’t drain all the water then go back and check your work.

Replacing and removing cast iron guttering

Choosing a replacement

Assuming you won’t be using cast iron again – you’ll have a job getting hold of it and even more of a job putting it up, apart from the fact that it’s expensive – your choice is between aluminium and plastic. Plastic guttering is made of UPVC (unplasticised polyvinyl chloride).

It’s probably the better choice for a do-it-yourself installation: it is far more widely available than aluminium, and has the edge in terms of cost and durability. Two different cross-sections are commonly available – half-round and ‘square’.

The latter is often given a decoratively moulded face similar to the more ornate ogee cast iron guttering. In addition, a semi-elliptical guttering is available – it looks a bit like half-round but is deeper and more efficient. This, together with some brands of conventional profile, can be camouflaged by being boxed in with a clip-on fascia panel. Which type you choose is largely a matter of personal taste, but try to choose something that blends into the style of your home.

More important than looks is the size of the gutter. Too small, and it will be forever overflowing; too large, and you will have paid more for the installation than is necessary. It’s all to do with relating the amount of water the guttering can carry to the amount of water likely to come off the roof during a heavy rainstorm. These calculations are complicated, but you can assume that they were done when the guttering was originally installed. Just measure the existing guttering at its widest point to find its size, and buy the same again. The most commonly available sizes are 75mm (3in), 100mm (4in), 112mm (41/2in), 125mm (5in), and 150mm (6in).

If in doubt, consult the manufacturer’s literature or get the London Roofers to do it. The actual cross-section of the gutter may vary from brand to brand; this can make it difficult to join with existing guttering: for example, the guttering belonging to a neighbour on a semi-detached or terraced house. Most firms offer adaptors to link their product with cast iron guttering, or with a different size from within their range.

However, they tend not to offer adaptors to tie in with the equivalent size from another brand, so if possible stick to one brand throughout the installation. If you have to link up with a neighbour’s gutter, find out which brand was used, and try to use the same. There are many different fittings as well as lengths of guttering available on the market. Before you start buying your new guttering get hold of a manufacturer’s brochure from the stockist you use and carefully check to ensure you have all the fittings you will need. Make sure you understand how the particular system works before you buy anything.

Taking down old guttering

Cast iron guttering is heavy, and may also be rusted into place, so removing it can be tricky. But there is no need to be gentle with it: it doesn’t matter if it breaks. The important thing is to work in safe conditions. If you are wrenching things apart, do it in a controlled way so you don’t fall off the ladder, and so that great chunks of gutter don’t fall down. Try not to drop cast iron guttering to the ground: it shatters easily, and, if it lands on a hard surface, dangerous fragments can fly off. If you toss the guttering clear of the house you might overbalance and fall off the ladder, so aim to lower larger sections gently to the ground with a rope. Begin with the section linking gutter and downpipe.

Cut through the old bolts holding the sections together. Then, if you lift the gutter slightly, you should be able to pull it free from the downpipe. Once it’s out of the way, unmake the joints between the sections of gutter (as if you were repairing them), and lift the guttering off its supporting brackets. It may, of course, be screwed directly to the fascia board. You can now turn your attention to the brackets themselves. These are usually screwed to the fascia board just beneath the eaves of the roof, and can either be unscrewed or levered off with a claw hammer. In older houses the brackets may be screwed to the tops or sides of the roof rafters, to support the weight of the iron guttering. If there is a fascia board to which you can fit the new gutter, the ends of the brackets can be hacksawed off. Otherwise, you will have to lift off some of the roofing to remove them. When all the old guttering has been removed, inspect the fascia board to make sure it is sound and securely fixed. If it is, fill the old screw holes and paint it before fixing the new guttering. If it isn’t, it will have to be replaced.

Roof guttering sagging and Leaking joints

Coping with sags

If a section of guttering has sagged, making it lower than the top of the downpipe, the water will not drain away properly. And you will be able to see this from puddles of water collecting in the guttering itself. You must decide whether to raise the sagging section, or lower the mouth of the downpipe to bring everything back into line.

If you flex cast iron guttering more than about 25mm (1 in) you’ll break the seal on the joints, causing a leak. So choose the option that involves moving the guttering least. In order to reset the guttering to the correct gradient you’ll need to fix a piece of string taut between two nails hammered into the fascia board.

Cast iron guttering repairs

You can then use this as a guide as you reposition each gutter support in turn. Leaking joints Joints in cast iron gutters are made by overlapping the two lengths of gutter, and bolting them together with a layer of sealant in between to form a watertight sea!. As this sealant begins to deteriorate with age, the joint starts to leak. To make the repair, first remove the bolt holding the joint together. Often this is too rusty to undo, so hacksaw off the bolt between the nut and the guttering, or drill out the rest of the bolt. Lever the joint apart with an old chisel, and scrape away all the old sealant. Clean up the joint with a wire brush, then apply a finger-thick sausage of new sealant and bolt the sections back together using a new nut and bolt and a couple of washers. Scrape off any sealant that has oozed out before giving the repair a coat of bitumen-based paint on the inside of the gutter.

GUTTER SIZES
Plastic gutters come in three common sizes (measured as the width from lip to lip):

• 75mm (3in) – for extensions and outbuildings

• 100mm (4in) – for most house roofs

• 150mm (6in) – for house roofs of very large surface area The 150mm size carries roughly seven times the volume of water that the 76mm size can take, and three times as much as the 100mm size.

A CAST IRON ALTERNATIVE

It is still possible to buy a new cast iron guttering in several ‘classic’ profiles as a match for existing gutters, but it’s expensive and very awkward to install.

Repairing and Replacing Roof Guttering

The chances are you won’t realise there is anything wrong with your home’s guttering until it leaks.

The gutters on your home are supposed to capture all the rain falling on the roof and channel it to one or more downpipes. In turn these downpipes take the water into the main drain, a storm drain, or to a soakaway in your garden. This efficient removal of rainwater is important to keep your outside walls sound. Any missing, damaged, or blocked guttering will result in water cascading down the face of your wall, leading to dampness, and eventually mortar and brick decay.

You may be able to repair it; or you may be faced with having to replace whole sections or the complete system. Until the mid-1940s most guttering was made of cast iron, although asbestos enjoyed a brief popularity. Cast iron had the disadvantage of being very heavy to work with – as you’ll find if you take some of it down. It is also prone to rusting if not properly maintained. Asbestos was heavy, unhealthy,looked rather bulky in appearance and was easily damaged. When plastic piping and guttering was introduced, it became an obvious choice. It is light to work with, doesn’t need painting and its smooth surface allows water to flow through it more effectively. In any case, cast iron is very expensive these days, and not particularly easy to obtain.

Blockages

You should check why a blockage has occurred in the first place. This may be due to sagging, or poor installation preventing a free run for the water. Or the blockage may be combined with a faulty joint which may be possible to repair. But if cast iron guttering is at all cracked it needs replacing. If your gutter overflows during heavy rain, the chances are that it’s blocked with leaves.