Recommended builders & tradesmen in London
Month: April 2013
Building brickwork arches
• Types of brick arch
• Designing an arch
• Choosing the correct bricks
• Erecting and reinforcing a Soldier arch
• Ringed arch construction: building plans, erecting a former and bricklaying
• Pointing and finishing off
First measure across the opening and note the proposed position of the bricks (do this on both sides of the wall if you are erecting two arches). Using this information, try to place the key or middle brick—directly over the centre of the opening and so avoid having to place a shorter, cut brick at one end of the arch. Mortar each brick into place carefully and place a straightedge across the face of the wall while you are building to ensure that the arch is correctly aligned. When you have finished, leave the mortar to set for three to four days.
Then carefully life-size plan of the intrados arc on a large piece of paper or card. Measure across the springing line at the top of the opening, then go to the paper and draw a line of the same dimension across the bottom of the sheet. Mark the midpoint of the line carefully and this will give you the striking point of the arch. With this, the base line of the arch, marked, use the striking point as a centre and draw a semi-circle above the springing line with a large compass or a pencil tied to the end of a piece of string. Then lay a square or protractor along the springing line and draw a line up from the striking point which bisects the half-circle.
This gives the exact position of the key brick. Use the half circle and the perpendicular line running up through it to mark the position of each brick on the plan. Make sure all the bricks face inwards towards the striking point and that they are separated by neat, wedge-shaped joints. Once the plan is drawn out—using one or more rows of brick—it can be used to calculate the exact number of bricks needed to complete the job. Remember, though, that the total has to be doubled in a cavity or double thickness wall where the arch has to be reproduced on both sides of a door or window opening.
Former construction: To construct the former, you need a sheet of 15mm plywood to make up the rounded sides and the soffit plus a piece of hardboard to go across the top. Mark the two semicircular side pieces first, to the same dimensions as the plan. Cut them out carefully using a fretsaw. Then cut a third piece as wide as the soffit—excluding the two side sections—and as long as the opening. Attach the three pieces together by nailing along the bottom of the two side sections into the edge of the soffit section. With the frame completed, pin a piece of hardboard as wide as the soffit across the top and make sure that it is flat and level with the two sides . After you have rechecked the former against the original plan, locate it in position across the top of the opening.
Supporting the former: To hold the timber former in place during construction, you must build a small frame to fit underneath. This should consist of two side pieces with one wider cross-piece which fits across the top—although in the case of particularly wide soffits two frames may have to be built, one for each side. First measure the distance from the ground to the springing line. Subtract the width of the cross support, then cut two side bearers from 50mm square timber to this size. Fix the side bearers to the brickwork in the middle of the soffit using masonry or galvanized nails. Next, lay a piece of flat plywood almost as wide as the soffit across the top of the side bearers. Check carefully that it is correctly aligned with a spirit level and then place the timber former on top. Finally, cut four folding timber wedges and drive two from each side between the cross-piece and the side bearers. These allow you to make minor adjustments to the position of the former during construction and make it easier to remove it after the mortar has set.
Building the arch: To help keep the arch brickwork level with the face of the wall, nail four flat boards about 500mm long on each side of the opening extending from the top to the bottom of the arch. Then attach a string across the bottom of each pair of boards to act as a guiding line this can be moved up as building progresses. Start at the bottom of the arch, building each side at the same pace. As you position each brick check— with the help of a line stretched up from the striking point—that it is correctly positioned according to the original plan. Try to make neat, wedge-shaped mortar joints between each brick by putting more mortar on one end than you do at the other. Alternatively, insert small wedging pieces of slate between each brick and leave them permanently to set with the mortar.
Continue upwards until you reach the key brick, raising the guiding lines as you go. Check carefully that the final bricks are positioned correctly, especially the key brick which sits directly above the middle of the opening. Leave the mortar to set for at least three to four days—then knock away the folding wedges and remove the former. Finally, pull the side supports away from the wall and point the brickwork on the arch. Take great care when you are building or rebuilding the brickwork around the top of the arch, and use the lines you erected earlier as guides. Try to ensure that each brickwork course meets the sides of the arch neatly, and cut any bricks to fit with a hammer and bolster. Point around the outside of the entire area and then while the mortar is still wet run a soft brush across the surface.
Removing a fireplace and blocking up the opening
Removing a fireplace and blocking up the opening is a relatively straightforward job providing you plan the work carefully and have the right tools and equipment to hand. If you don’t want to pay for professional builders in London, we offer you a small guide.
To remove the surround, hearth and fireback use a crowbar, club hammer and a bolster. These should be adequate for prising the various parts free of their fixings without the need for excessive force, but you will need safety glasses or goggles if you have to hack away mortar with the bolster since loose material is bound to fly. Where the surround is screwed to the wall or chimney breast you also need a large screwdriver, plus a hacksaw to cut through any fixings which cannot easily be shifted. Bear in mind that the hearth and surround are likely to prove heavy and you will need the help of at least one other person to dispose of them.
An assistant can also help by steadying the surround while it is being levered free of its fixings. Once all the equipment has been assembled, clear the room ready for the work. Removing the fireplace will create a great deal of rubble and dust, so it is best to take everything out of the room, including the carpet. Sheet polythene can be bought in large rolls to completely cover the floor and protect it while the work is going on. If the fireplace is near flat surfaces such as window ledges or built-in furniture, cover these with newspapers and masking tape. A number of heavy-duty polythene bags are useful for disposing of the loose rubble and soot created during demolition and clearance of the site.
Removing the surround
Since the surround is likely to be resting on top of the hearth it is best to start by removing this. The technique you use will depend on how the surround is constructed.
Tiled surrounds:
Here the first task is to remove the plaster covering the two fixing lugs. To do this start at the top right hand corner of the fire and chip away the plaster using a hammer and bolster. When you have uncovered the fixing lugs, ask a helper to steady the fire surround while you undo them.
Sometimes they will simply unscrew from the wall; if not, cut them off at or near their junction with the wall using a bolster or hacksaw. With your helper still steadying the far end of the surround, use your left hand to steady the other end and hold the crowbar in your right hand. Insert this between the surround and the chimney breast, somewhere near the base. If the surround moves by even a few millimetres there are no more fixing lugs. If not, there may be fixing lugs at the bottom edges which should be removed before you proceed. Once you are sure that all the lugs are free, slowly lower the surround to the ground in front of the fire. Two people can usually carry the surround outside to be disposed of, but i f you have to negotiate a stairway or an awkward doorway, get some extra help.
Removing a timber surround:
The procedure used to remove a wooden surround is much the same as for a tiled one except that the fixing lugs usually face towards the fire opening rather than outwards away from it. Start by taking the crowbar and driving it between the wooden part of the surround and the brickwork behind it. By levering with the crowbar and using your hands to pull the surround away from the wall you should be able to open a gap between the surround and the wall big enough to look down.
Check whether the timber is held in place by any other fixings—either metal studs or bars. If not, simply lever the facing away from the wall and pull it clear. If there are other fixings, work your way around the edges of the facing gently levering it away from the wall; do this a small amount at a time to avoid damaging the wall and cracking the brickwork. If the fixings refuse to pull clear, insert a hacksaw between the facing and the wall and cut through the studs or bars.
Removing a brick surround:
A stone or brickwork surround is easily removed with a hammer and bolster one course at a time. Starting from the top, insert the bolster into each of the layers of mortar. Then gently tap each brick free and remove it by hand, out of the way. You may come across steel ties bridging the two walls in which case work these loose by knocking them gently backwards and forwards with the hammer then pull them free with your hand. Continue downwards removing the soldier arch and steel support as you go until you reach the fire hearth.
Levelling the hearth
Most hearths consist of a slab of concrete—usually covered in tiles— which sits below the opening and is bedded into place on a weak limemortar mix. If the bottom of the hearth is level with the surrounding floor loosen the bedding mortar by chopping around it with a hammer and bolster. Then insert the crowbar under one end of the hearth and raise it high enough to push a thin batten of wood underneath. Do the same with the other side and you should be able to lift the whole hearth away with the help of another person.
However, if the hearth is lower than the surrounding floor, you have no choice but to break it up or chip it away down to the required level using a hammer and bolster. Removing the fireback The fireback is usually held in place by a bed of mortar laid against the edges of the opening. It is usually old and crumbly so if it does not immediately pull free, use the hammer and bolster to break it into more easily handled pieces. The cavity above will be full of soot and rubble and you should make sure that this is removed and the opening brushed clean before you continue.
Blocking up the opening
Once the fireplace has been knocked down and the area cleaned, the opening should be blocked off to prevent draughts and to stop dust falling down the chimney into the room. For this you can use bricks, lightweight building blocks or more lightweight materials such as hardboard, chipboard or asbestos. In order to bed the blocking material into place and allow a neat plastered finish, you need to cut away some of the existing plaster around the opening with the hammer and bolster.
If you decide to retain the present surround, first break out the fireback and then cut away the plaster around the opening to a distance of about 200mm on each side. Try not to damage the brickwork underneath as you do this and leave straight edges around the area you have cleared away so that final plastering is made easier. What you do next depends on whether you block up the opening with bricks or some type of sheeting. But whatever method you use, the blocked opening must contain a ventilation grille, fitted at a distance of about 100mm from the floor.
Bricking in:
Bricks and lightweight building blocks are both perfectly adequate where you want to block up an opening permanently. But if the opening is particularly small, bricks are preferable since they are easier to manoeuvre and fit into place.
First prepare a mix of 1:4 mortar and lay a bed of it on the floor between the existing wall. Then build up each course of bricks.; remember to leave a gap 100mm from the floor to accommodate the vent. As the wall is built upwards, hold a straightedge against the face of the brickwork to check vertical and horizontal alignment. Any bulges and indentations should be corrected and adjusted before you continue.
Build up successive courses until you fill the cavity. The gap on the last course may be too thin to take whole bricks, so you should cut them lengthways to make up the difference. Finally, look over the new brickwork and fill all gaps to create a smooth and flat surface. Leave it to dry out for 12 hours before plastering. Boarding up: For this use 6mm oiltempered hardboard, chipboard, or if you intend to fit a gas fire in front of the wall, asbestos sheeting. Measure and cut the sheeting to size, and make an internal hole to take the ventilator using a drill and a padsaw. When cutting and drilling asbestos, make sure you wear a mask to avoid breathing in the dust. Fix the sheeting into place by marking and drilling holes along its edge and using wall plugs to secure it to the wall beneath. If necessary pack it out to bring it nearly level with the surrounding plaster.
Replastering
Before plastering make sure that the surface is prepared properly and that old and flaking plaster is stabilized. Check brickwork for loose mortar: strengthen any crumbling joints then chip away excess mortar once this has dried. Try to plaster the area neatly by feathering off around the edges. Once both coats of plaster have been applied and allowed to dry thoroughly, the ventilation grille can be fitted and fixed firmly in place with bolts or self-tapping screws. Although the plaster may dry hard after about 20 minutes, it often takes months to settle on the brickwork below; consequently, redecorating, especially with wallpaper should not be undertaken straight away.
Sealing
Disused fireplaces often run the risk of penetrating damp as a result of rain falling down the chimney. The simplest way of avoiding this is to fit a rain bonnet, a blocking piece which is cemented into the chimney pot. The bonnet effectively stops rain entering the chimney, but allows air to circulate freely. Alternatively, you could remove the chimney pot, cover the opening with slate and then seal it with mortar flaunching.
In this case, though, ventilation must be provided in the form of an airbrick in the chimney stack. The brick should go as high as possible, preferably in the roof space. Note that in the UK, sealing a chimney constitutes a structural alteration and you will need building permission from your local Building Control office or District Surveyor. He will want to know how the sealed chimney is to be ventilated and also what alternative methods of heating are being used.
London powers ahead of the UK
London is home to over eight million people. It is also called the capital of the world. The economy of the city itself, it is extremely unconnected to the rest of the United Kingdom, a Vatican style cosmopolitan city. At a time when the rest of the UK and Europe suffers from job loses and property prices falling, London seems to be immune to the economic recessions that plagues the rest of the world. The employment is rising in London according to the latest figures, balancing the figures for the rest of the United Kingdom, where job loses are increasing.The property market in London is a perfect example to illustrate the contrast between the city and the rest of the UK.
The properties in London alone, are worth more than the rest of the United Kingdom added together. Investors from all over the world, from Russian oligarchs to anyone who has money to invest follow the principle : safe as houses and invest in the brick and mortar business. London Olympics also helped grow the economy of the city state like, despite the recent riots. Massive construction projects have taken place, and many more are being planned by architects. Building works like the Shard , the Olympic village , Crossrail project, etc , are providing the city with investments into the property market and infrastructure.
And then there is of course, The City of London , the truly financial capital of the world, home to the bankers and financial business. Statistics show that most Londoners contributes 70% more to the national budget than the rest of Britain. But there is also a darker side to the statistics. The quality of life for Londoners is well below the standard for the rest of the UK. People work harder and longer, the so called rat race is the norm and everything is more expensive. For most homeowners in London, maintaining a property will cost them about 40% more than the rest of the UK. A plumber or an electrician will charge a small fortune and the cost of building a house extension or a loft conversion in London, can buy you a whole street in Liverpool, where £1 houses were put on sale recently by the local council, on the condition that the buyer will refurbish the property and has experience in a building trade.
In London, Battersea Power Station has been purchased by foreign property development and a decent sized apartment is expected to cost more £ 1 million. Because of the high demand of residential properties in London, some 800 apartments have been promised to be sold to British buyers, but foreign buyers will have the chance to buy a flat ahead of British buyers from London. The wife of the new governor of the Bank of England, recently complained that is impossible to find a place to live in London having a budget of less than one million. This summons the development of London in the United Kingdom, a two speed economy in a single country.