RESTORING BRICKWORK

Fair-faced brickwork makes an attractive interior wall surface and a striking alternative to the usual smooth plaster with its paint or wallpaper finish. Here’s how to get that finish.

Brickwork is full of visual interest, and can vary greatly in colour, tone and texture from light-coloured, regular and smoothfaced machine-made bricks to warm-toned, multi-coloured, rustic hand-made stock bricks. But before you start chopping away the plaster to uncover the brickwork beneath, stop to consider some of the possible problems. The most obvious thing to check is whether there actually is brickwork behind the plaster; the wall may be of building blocks, and quite unsuitable for stripping. The simplest way to find out is to drill, and then to examine the dust. If it’s red or orange, you’ve hit brick; if grey, it’s a block wall. Your first hole may strike mortar, not masonry; carry on drilling holes until the dust colour changes to red or grey.

Assuming you do have solid brickwork, you now want to know if it is worth stripping the plaster. Often the bricks used in walls which were originally intended to be plastered have not been selected for their appearance. They may also have been laid to comparatively low standards of regularity, with very untidy mortar joints and a lot of broken pieces of brick. To find out whether the standard of material and workmanship underneath is good enough to warrant revealing you will have to strip off a small area of plaster. If the bricks have been keyed for plaster (with grooves cut into their faces) this creates another problem. Removing the plaster will be very difficult, and the face of the bricks will look untidy even when completely cleaned off. You will find this almost impossible to remedy without rebuilding the wall.

Any electrical switches, wall lights or power points on the wall will have associated wiring, probably in chases or grooves cut into the brickwork behind the plaster. If this is the case you may have to remove or re-run some of the wiring to give a neater appearance. If there are a lot of chases to make good, this could be very difficult to do without causing unsightly blemishes.

You must also consider whether stripping the wall will lower its fire resistance or the degree of sound insulation (especially important with common party walls between attached houses). It’s advisable to check up on these points by contacting your local authority’s Building Control Officer. You should also look out for any special lining or rendering used on the wall to prevent rising damp from affecting the plaster; this should obviously not be removed. Before starling WUIK, remove carpets and any other floor coverings; lay down polythene sheets to catch the debris. Preferably attach these to the base of the wall by stapling or taping them to the skirting boards. If possible clear the whole room of furniture because stripping the plaster is a very dusty job.

You have to remove the plaster with care, as it’s easy to damage the underlying brick surface. Tackle this job by hand, with a sharp 100mm (4in) bolster chisel and a club hammer. Wear a pair of stout gloves to protect your knuckles from mis-hits with the hammer and a pair of safety spectacles or goggles, as chips and grit will fly everywhere. If you are right-handed, work from the top right-hand corner of the wall and chop away a small area to reveal a brick or two. Then work outwards, with the bolster held almost parallel to the brick surface. The bolster blade should be sharp, as the object is to skim along the surface of the brick to split off the plaster in sheets and not to pulverise it.

Resist the temptation to be heavy-handed with the hammer. Patience and care is needed, and there’s no really effective substitute for hand tools. An electric power hammer with a bolster bit may seem the ideal tool, but remember it needs to be used with great skill if you are to avoid damaging the brickwork.

If the brickwork beneath has been covered with whitewash, removing this will take time and a great deal of perseverance to achieve good results. Chemical paint strippers (the water-washable type) or a solution of (1 part to 5 parts of water by weight) may be worth trying. The cleaning agent should be brushed on, and time allowed for the paint to soften. It should then be removed by gently scrubbing. Once the brick surface begins to show through, that particular area should be wetted with water before continuing any further application of the solvent on or at the edges of the area. Old limewash which has had many coats is particularly difficult to remove and may need to be soaked with water over a long period to soften it.

If gloss or emulsion paint has been used, you won’t be able to strip it successfully by any means. The only answer is to clean down the wall surface and repaint it.

Making good the brickwork

Once the plaster or paint has been removed, the wall face should be made good by repairing the mortar joints where necessary. Start at a top corner of the wall, working across and downwards so that the surface is kept clean. If you decide to repoint the whole wall, colour becomes a major consideration. The final tone of the brickwork will depend on both the type and colour of the joint. Natural sand and cement dries to a fairly light colour, and therefore the brick itself appears darker by contrast. Conversely, a dark mortar produced with a colouring pigment will effectively lighten the brick tone. Matching the mortar with brickwork of a single colour gives a flat appearance because there is no contrast between the two materials. To add interest use a mortar colour which contrasts with that of the brick. With multi-coloured bricks, a mortar matching one of the colours in the brick produces an ideal balance.

Which type of joint you choose for report-ing depends largely on your personal taste -and how much time you have at your disposal. A slightly recessed joint (produced with a bucket handle or piece of garden hose), or even a raked joint, is relatively easy, quick to do and looks good. Brickwork with raked joints will appear darker because of the shadows cast at the joints; and the texture and form of the bricks themselves will be more pronounced.

Your choice of joint profile may also depend on where the wall is. For example, a rough surfaced wall with raked joints is not suitable for a kitchen, where grease can accumulate in the crevices: a flush joint would be better.

Holes in the brick surface can be repaired using a mixture of filler (the type used for car body repairs is ideal) and brick dust scraped from the bricks to be repaired. Make it into a thick paste and press it into the hole. If the hole is a deep one, you will need more than one application of the filler to get a level surface (use plain filler except for the final layer). Unlike car repair applications, at no time should the filler stand proud of the surrounding surface as any attempt to file or grind the surface level may result in the patch acquiring a greyish-white tinge and becoming quite obvious to the eye.

Painting brickwork

If the colour of the uncovered brickwork is patchy and unattractive, or you are unable to remove all traces of plaster or paint, then the texture and pattern of brick can still be retained if the surface is painted.

Emulsion paints are your best choice. Apply the first coat as a primer (thinned down with an equal volume of water) to even out the suction rate of the wall surface. Then apply two full-strength coats with a brush; even a long pile roller will not cover the mortar joints unless they are virtually flush.

TIP: PREPARING THE ROOM

Before you start to strip off the plaster from your wall it’s wise to roll back your floorcovering and lay down sheets of thick-gauge polythene to catch the debris. Staple or tape the sheets to the top of the skirting so no bits can get into the edges, where they will be difficult to remove.

REPLACING A DAMAGED BRICK

The appearance of your stripped wall will be marred if there’s a cracked or chipped brick. To replace it:.

• chop out the pointing round the brick with a cold chisel and club hammer.

– wiggle the brick free: break it up if it won’t come out easily

– mortar in the new brick (or an old one chosen to match the wall) using a mix of three parts sand to one part cement with a plasticiser added to make the mix workable

– copy the pointing profile used on the rest of the wall using a pointing trowel.

Drying out

After any treatment has been given which introduces water into the wall – even re-pointing – you must allow it to dry out thoroughly before attempting to seal it.

The drying time will tend to depend on the porosity of the brickwork (how much water it will absorb) and the drying conditions. With very absorbent bricks, even with good central heating and ventilation, it will still take something like two to three months before the wall is in a suitable condition to accept a sealing coat. If you attempt to paint or seal the surface while it is still damp, ‘efflorescence’ will result, and this will ruin the finish. Efflorescence looks like white powdery patches on the surface of the bricks, and it happens because moisture in the wall carries chemical salts from the brickwork or mortar to the surface.

With bricks of low absorption, of course, the period for drying will be somewhat shorter – two months is a safe maximum. If, after drying, the wall does not have the brightness you want, you could try lightly grinding the surface by hand using either a coarse sanding block or else a hard brick which has a rough textured surface. Alter- natively, a power drill with a suitable circular grinding disc may be used. It’s another extremely dusty job, so wear goggles and a mask, and keep doors closed and furniture covered.

Removing the existing surface of brick-work in this way inevitably changes its texture, so you should test a small area before attempting to treat the whole wall. Having brought the surface up to the point where it is visually acceptable, the excess dust should be removed with a stiff brush. If you have a set of extension tools for your vacuum cleaner, use these to remove the last of the dust.

Sealing brickwork

Sealing internal brickwork can be carried out when the brickwork has thoroughly dried out. It is not, of course, essential to seal interior brickwork, but the process of treating the brick surface stops it dusting or shedding particles and makes it resistant to staining. You can use either a polyurethane varnish, or else a silicone water-repellent sealer of the type more commonly used on exterior masonry. If you Ye using varnish, a matt finish looks better than a gloss one.

The procedure with varnish is to prime the surface with a solution of equal parts of varnish and turpentine, in order to prevent rapid and uneven absorption of the first full coat. If you find, as may happen with very porous bricks, that the surface is still absorbent and does not cover evenly with neat varnish, a second diluted coat should be applied and allowed to dry before con-tinuing. The neat varnish can then be evenly applied with a brush over the whole surface. This coat should be tack-dry in four hours and ready for a second coat if necessary. You can judge whether a second neat coat will be needed by the evenness of the surface appearance, and by the degree of absorption of the previous coat into the pores of the brickwork. Don’t apply a second coat if the surface has been treated successfully with a single coat as there’s a risk of ending up with a glass finish – which would be quite out of character. You may need to consider dusting down and resealing the surface after a period of four to five years. But otherwise the wall surface will provide a very attractive feature which requires virtually no maintenance or redecoration, just an occasional wash.

HIDING THE CEILING JOINT

When you’ve stripped the plaster from your wall you’ll be left with an ugly gap at the ceiling, where the papered or painted surface stops short. To hide the gap:

• nail lengths of wooden quadrant beading to the ceiling joists.

• fix pre-formed mouldings in the angle. They’re made of plaster, glass fibre, plastic, plasterboard and wood in traditional and modern styles. Most can simply be stuck in place with adhesive.

REPLACING THE SKIRTINGS

Skirting boards are usually secured to the wall with ‘cut’ nails driven into timber ‘grounds’, which are fixed to the wall flush with – and below – the plaster finish. When you remove the plaster the skirting board will stand proud. To refix it:.

– prise away the skirting and grounds using a bolster chisel and club hammer before you hack off the plaster.

– hack off the plaster from the wall and treat the surface as required

– refit the skirting directly to the brickwork using 63mm (21/2in) long countersunk woodscrews driven into wallplugs (don’t use nails; they’d just work loose in time). With deep skirtings, use two screws at each fixing point.

– recess the screws in counterbores and make good the hole with wood filler so that the screw heads won’t show.

– repaint the skirting.

Sorry, comments are closed for this post.