Staircases

Filed Under: Do it yourself, Home repair, Redecorating, Remodeling    by: ITC

Staircases are often taken for granted yet they are complex pieces of carpentry which give many years of trouble-free use. They rarely need replacing: just as well, since they are often tailor-made to fit. Even so you can buy ready made versions, which cater for common storey heights and these can often be easily adapted to fit exactly.

A staircase comprises a number of steps fixed between two long boards which are fixed to the joists of the floors they connect. These boards are called strings, the horizontal surfaces of the steps are called treads and sometimes they have vertical boards between them known as risers.

Strings can be in two forms: closed and cut. With the former the ends of the treads and risers are housed in shallow slots cut in the face of the string and held there by wedges driven in from behind and below. The risers are fixed to the treads below with housing joints or screws, and to the treads above by triangular blocks glued and nailed in place. The top edge of a cut string is shaped to provide horizontal ledges to which the treads are fixed. Sometimes both foul’s of string will be used in the same staircase, the closed string being fixed against a wall with the cut string on the outside.

Further support for the steps can be provided by a beam that runs below the treads and risers parallel to the strings. This is known as a carriage.

There are two basic types of staircase: the closed tread and open tread. Of the two, the former is most common, having treads and risers in a boxed-in construction. The underside of the strings are usually clad with lath and plaster or gypsum board or there may be a closet below the stairs. The latter is preferable since it allows easy inspection and repair. The open tread staircase has no risers and is completely exposed.

In a closed tread staircase the treads are about lin thick and will overhang the risers by a similar amount, their leading edges or noses being rounded off. A decorative molding is often fitted below the nose. An open tread staircase will tend to have thicker treads because they are not supported by risers, although sometimes a batten will be set on edge immediately below them to stiffen the tread.

All staircases must have at least one handrail and if wide they must have one on each side, depending on the requirements of your local code. The handrail forms part of the balustrade, the other parts of which are the newel posts and balusters.

The newel posts fit at each end of the stairs with the handrail running between them. Not only do they support the handrail but often the strings as well which will be slotted into them and fixed with wooden dowels. Further support for the handrail is provided by the balusters which fit between it and the strings.

Though straight staircases are common, where space is limited it is often necessary for the stairs to change direction on the way up. A small quarter landing is used to provide a 90° change of direction and a half landing will turn the stairs back on themselves.

If there is not room for a half or quarter landing a turn can be put into the stairs by inserting triangular treads called winders. Winders are also used in spiral staircases which can be great space savers. Unfortunately they are not very practical since carrying furniture and other bulky items up them is difficult.

Covering Roof with Asphalt

Filed Under: DIY Outdoor, Do it yourself, Home repair    by: ITC

The method used for constructing a flat roof is outlined in the following way; the joists usually being laid along the length of the extension from the house to the end wall. At the house end, the joists may either rest on top of a wooden wall plate, being toe-nailed in place, or be nailed to metal hangers which are also nailed to the wall plate. The ends of the wall plate are set in sockets built into the extension side walls.

At the end of the extension, the joists can simply rest on top of the end wall and be nailed in place or, if there is a window in the end wall, a second wooden beam can be fitted to span the opening and support the joists.

Tapered furring pieces are nailed to the tops of the joists to create the right fall. For felt covering the fall should be 1 in 60, but for asphalt it should be 1 in 80.

Sheets of exterior grade plywood are used to provide a roof decking and are nailed down through the furring pieces into the joists. The sheets should be staggered so the joints between their short edges do not coincide.

Although a felt-covered roof is the cheapest and easiest to construct, a much more durable finish can be obtained by having it covered with asphalt. This material is heated until it melts and is then spread over the roof to provide a solid, impervious layer when it cools. It is a job that requires a great deal of skill and is one that you should get a building, contractor to do for you.

Flat roofs can often suffer from condensation when moist air passes through the ceiling from the rooms below and cools on contact with the underside of the roof — particularly with bathrooms and kitchens and when the atmosphere is damp.

Leaving ventilation gaps behind the fascia and insulating the roof will help, but the best idea is to either use foil-back gN,:psumboard for the ceiling – which will stop the moist air passing through – or staple a separate polyethelene vapor barrier to the underside of the joists before nailing the gypsum- board in place. Once the extension has been weatherproofed by glazing the windows and fitting the doors, the room can be finished. Before plastering the walls and ceiling, lay in the necessary electrical cables, mount accessory boxes and run in any pipe work for hot and cold water or central heating.

Directions

1 Nailing the roof joists into hangers attached to the main beam; toe-nail through the top of the roof joists into the main beam also.

2 Nailing furring pieces (narrow end over the front wall) to the tops of the roof joists to set a 1 in 80 fall for the roof

3 Nailing the plywood roofing sheets over the furrings: stagger the joints between the short edges.

4 After pouring hot asphalt onto the roof. smoothing it out to a layer about 3/8in thick.

Fitting a New Ceiling

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

Gypsum board for ceilings comes in two thicknesses: 3/sin and 1/2in, the former being suitable for use where the joist spacing is no more than l8in and the latter where the joists are up to 2ft apart. The standard sheet sizes are 8 and 10 x 4ft. You may find the smaller sheets easier to handle and you can cut them in half to make them even more manageable. The edges should meet on the joist centerlines, so you will probably have to trim them slightly anyway.

The first job is to nail lengths of 2in sq or 2 x Sin wood along the walls parallel with the joists so that its lower edge is level with the undersides of the joists. Then fit more short lengths of wood to the walls between the ends of the joists to provide support for the edges of the boards.

The sheets of gypsum board must be fitted with their long edges at right-angles to the joists. Toe-nail more lengths of batten to act as bracing between the joists so that the inner edges of the sheets will fall on their center lines. A length of batten marked with the board width will help position them accurately.

Finally, mark the position of each joist on the walls as a guide for nailing the sheets in place.

To cut sheets to size, use a utility knife and steel straightedge. Cut down through one face of the board, snap back the waste against a batten and run the knife blade down the crease from the other side.

If you intend plastering the ceiling, fit the gypsum- board gray side down. For painting or papering directly over the top, leave the ivory side showing.

Holding large sheets of board against the ceiling for nailing can be difficult so nail lengths of 2 x lin batten together to foiiu T-shaped props with which a helper can support it while being nailed in place.

Nail the first board in place, working from the center outwards and spacing the nails at 6in intervals. Drive them home so that they just dimple the surface; to be filled later. Use 11/4in gypsum board nails for thinner sheets and 11/2in for thicker kinds.

Continue in this way, working across the ceiling. Keep any cut edges up against the wall, but if this is not possible make sure they meet on a joist with a slight gap in between for filling; stagger the joints.

When you have clad the entire ceiling, seal the joints between the sheets and, if you prefer, apply a thin skim coat of plaster.

Repairing an Old Ceiling

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

There are two types of ceiling construction, depending on their age. Early ceilings were made by nailing thin strips of wood (laths) to the joists so that there were narrow gaps between them. Plaster, often reinforced with animal hair, was then spread over the laths and forced through the gaps in between. The ridges so formed are called “nibs” and these hold the ceiling together.

The more modern method of constructing a ceiling is to nail sheets of gypsum board to the joists and cover them with a thin skim coat of plaster.

Cracks are the most common form of damage found in a ceiling and if they are only fine they can be filled with a filler compound. However, if they are wide and cover a large area of the ceiling the structure will be dangerously weak and should be replaced.

If a plasterboard ceiling sags it is probably because the fixing nails have loosened. Refix the affected area by renailing with 2in drywall nails spaced 6in apart.

If plaster has fallen away from the laths but they appear to be in good condition, replaster them after cutting back the original plaster to make a regular shape and reach sound plaster. Undercut the edges of the plaster and make sure there is no old plaster left between the laths. Then treat the area with an adhesive.

When plastering always work across the laths, spreading on a thin coat of bonding plaster first and keying it with a scratch comb made by knocking a row of nails into the edge of a short batten. Apply another coat of bonding plaster and key this with a devilling float, pressing it down to allow for two thin finishing coats. Polish these when hard with a wetted steel trowel.

Putting a Doorway in stud partitions

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

To put a doorway in a stud partition, first expose the framework below the skin of the partition. Find the stud positions on each side of the proposed opening by tapping the surface and probing with a bradawl. Draw in the stud positions on the surface and another line between them to mark the height of the door frame plus an allowance for the wood lintel.

Cut along this outline with a keyhole saw continuing the cut through the skin across the top of any studs or bracing you come across. Lever off the skin to expose the framework and the back of the other skin. Remove the latter in the same way.

Cut out all the framework within the opening and then make up two short “trimmer” studs to support the lintel. Nail the trimmer studs to the original studs on each side of the opening and the lintel to the tops of the trimmer studs. Nail through the lintel into the base of any cut stud.

If the door frame is narrower than the distance between the trimmer studs, fit an intermediate between the lintel and sole plate, linking it with short braces to one of the trimmer studs.

Cut out the section of sole plate across the bottom of the opening and fit the door frame. Finish the partition by nailing on gypsum- board and applying a skim coat of plaster over the top.

A hatchway between a kitchen and dining room can be extremely useful, and you may wish to consider installing one should you have to block off a redundant doorway, or to suit other remodeling plans. Plan its position carefully so that it coincides with a work surface in the kitchen and something like a worktop or small table in the dining room so that there will be somewhere to place dishes and plates, for example.

The method for making a pass-through is basically the same as that for making a doorway, except that the opening is not continued to the floor. In a wood framed partition, a wood sill piece is needed between the studs on each side of the opening.

The pass-through can be left open with plastered edges and a wood sill, screwed across the bottom or a wooden lining frame can be fitted to take hinged or sliding doors, or some form of roller blind to give the maximum amount of privacy, and also to prevent cooking smells, for example, from drifting through.

Plastering Corners

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

The main problem when plastering corners, whether external or internal, is getting a good, sharp angle. You will face a similar problem at the junction between the wall and ceiling. However, the techniques for dealing with both types of corner are not difficult to master.

There are two forms of guide you can use for forming an external corner: a timber batten or purpose-made metal beading.

The wooden batten is used as a thickness guide for the floating coat then the finishing coat on each wall. Nail it on to one wall so that it projects by the right amount beyond the other and use as a ground for that wall. Then, when the plaster has set, move it round the corner and repeat the process. Any sharp ridges on the apex of the corner should be sliced off with the trowel blade and then the corner rounded off with a block plane or rasp. With wallboard you must tape the angle first.

Two depths of metal beading are available to deal with masonry or gypsum board-clad walls and they can be fixed in place with plaster or galvanized nails. On wallboard, nails must be used. The beading acts as a ground for the floating coat on masonry walls. Before this hardens, cut back the level to allow for the finish coat. Trowel off flush with beading, leaving the nose exposed to provide a knock-resistant corner.

For dealing with internal corners, you need a long wood rule. Use this to rule the floating coat outwards from the corner.

After keying the floating coat, cut out the angle by running the corner of the trowel blade up and down it, holding the blade flat against each wall in turn. This will produce a sharp angle. The finish coat should be treated in the same manner. The final job is to hold the short side of the blade against one wall so the long side is just touching the fresh plaster. Hold the blade at 30′-40° and gently run it down the corner.

For finishing corners where both walls have been plastered, use a special V=shaped angle trowel. This produces a constant right angle in the fresh plaster. Load a small amount of plaster onto the angled blade of the trowel and run it lightly down the angle.

Directions:

1. Reinforcing the external corner of a masonry wall with angle-bead; set it into blobs of plaster, 12in apart.

2. Plastering one wall; work away from the corner, using the nose of the bead as a thickness guide.

3. Plastering the adjoining wall in the same way: leave the nose just visible. Score the surface of both walls.

4. Applying the finishing coat, this time covering the nose: round off the corner by running a wet finger along the bead.

5. Securing angle-bead to the internal corner with galvanized nails; nail through the drywall into the stud.

6. Applying a coat of finishing plaster, working away from the corner; the nose should be left visible in this case.

Plastering Wallboard

Filed Under: Do it yourself, Remodeling    by: ITC

You need only apply two very thin finishing coats directly over the drywall.

The plaster needed for the job is sold ready mixed or in a powder form requiring only the addition of water. It is mixed in the same way as other plasters and has a creamy texture.

Because you are only applying a finishing coat to the drywall board there is no need for thickness guides, except at any external corners.

It is a good idea to practice scooping the plaster from the hawk on to the trowel first, using a spare piece of drywall to try your hand at spreading the plaster and making it stick to the board_ The technique is to hold the hawk in your left hand (or right if you are left handed) so the top is level and set the trowel blade on edge, so it is at right angles to the top of the hawk. Use the trowel to push some plaster towards the edge of the hawk, scooping it off at the same time as tilting the hawk towards you. The whole is done in one smooth movement.

The first job is to seal the joints between the individual panels of gypsum board, reinforcing them with perforated paper tape or nylon tape to prevent the plaster cracking. The standard paper tape is available in 2in wide rolls of 50-500 feet.

Cut strips of tape to run the length of each joint, including any horizontal ones, before you begin plastering. They must be exactly the right length and should not overlap or be folded, otherwise the plaster will not grip the wall properly.

To seal the joint, spread a thin layer of plaster, about 4in wide, along it from bottom to-top. Hold the trowel so that the blade is at an angle of about 30° to the wall, reducing it as you move up the joint and the plaster on the trowel thins.

While the plaster is still wet, press the tape into it. The easiest way to do this is by draping one end over the blade of the trowel and pressing this into the plaster at the ceiling. Then gently slide the trowel down the plaster, positioning the tape with your other hand. Once the tape is in place, run the trowel carefully up the plaster to make sure it is bedded properly. Treat all the other joints between the panels in the same way.

When the taped joints have dried — which should take about 11/2 hours — fill in the areas between them with more plaster. Work upwards from the floor, spreading the plaster in thin vertical strips and being careful not to build up ridges at the joint positions. Stop just short of the ceiling and work downwards from there to get a clean, sharp angle.

Unless you are working on a very small area, by the time you have finished putting on the first coat, the area you started on will be ready for the second coat. This should be about 1/sin thick and applied with long, sweeping strokes to eliminate ridges. Start at the bottom corner of the wall and work upwards and along to make one continuous coating.

Allow the plaster to set slightly and then go back over it with a clean trowel to smooth off the surface. Finally, when it has hardened fully, “polish” the surface by splashing clean water on to it with a paintbrush (about 4in wide) then sweep the trowel back and forth lightly. This will give a smooth, matt finish ready for decoration.

Plastering Techniques

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

Plaster is an excellent and inexpensive material for giving a smooth, hard surface to an internal wall so that it is ready for painting or wallpapering.

There are many types of plaster, but they can be divided into two basic types: gypsum-based and cement-based. The former are used solely for indoor work, whereas the latter are mainly used outdoors for rendering walls. Cement- based plasters do have a use indoors. however, and that is to finish external walls that might be subject to damp penetration; damp will attack a gypsum plaster and cause it to crumble.

Modern plasters come premixed with lightweight fillers such as perlite or vermiculite, which give a higher degree of thermal insulation and fire resistance and should be mixed with clean water.

Plaster is normally applied to the wall in two layers. The first, called a “floating” coat, is intended to even out the irregularities in the wall surface, so it is kept fairly thick — about 3/sin being usual. The second, finishing coat is spread much thinner Ysin or so — and carefully toweled off to a smooth finish.

Different types of building materials absorb water at different rates and if too much water is absorbed from the fresh plaster, it will dry too quickly and crack.

For example, bricks and lightweight building blocks absorb water quickly and are termed high suction surfaces. On the other hand, materials such as concrete and gypsum board do not absorb water that quickly and are termed low suction. You must choose a plaster to match the surface; but if in doubt, the best thing to do is coat the entire wall with a bonding agent which will make a low suction surface.

Browning plaster should be used for the floating coat on high suction surfaces and Bonding plaster on low suction surfaces. Finish plaster can be used for the finishing coat in both cases.

Only buy plaster as you need it since it has a limited shelf life. A 22lb bag of Browning or Bonding plaster should cover an area of about 1.8yd2 at a depth of 3/sin. The same quantity of Finish plaster, spread thinly, should cover an area about 6yd2.

In addition to a couple of clean buckets and a long level, you will need some special plastering tools: a spot board about 3ft square and supported on trestles or an old table to hold the mixed plaster while you work; a hawk for carrying small quantities of plaster to the wall; a rectangular metal plasterer’s trowel: a wooden float for producing flat surfaces (with a few nails knocked into the end it can double as a “scratcher” for scoring the floating coat before applying the finishing coat): and a 5ft length of 1 x 3in planed wood for leveling the plaster surface.

Cleanliness is essential when mixing plaster. since any dirt present in the mix will affect the drying time. Always use clean tap water for mixing and have a separate bucket of water for cleaning the tools as you work.

Mix the plaster and water in equal volumes in a clean bucket, adding the plaster to the water by sprinkling it on top and breaking up any lumps between your fingers. When the water has soaked into all the plaster, use a thick piece of wood to stir the plaster into a smooth consistency, (Finish plaster should resemble runny ice-cream). and make sure there are no lumps.

Wet the spot board and turn out the plaster on to it, kneading it with the trowel. If the mix appears too wet, sprinkle on a little more plaster and mix in with the trowel.

Bracing the Stud of a Stud Partition

Filed Under: Do it yourself, Home repair, Remodeling    by: ITC

With all the studs of your stud partition in place, now fit the bracing. If you intend cladding the partition with standard aft sheets of gypsum board, place the bracing in a row 4ft from the floor. If the partition is taller than 8ft, a second row of bracing should be fitted to support the upper edges of the drywall panels and the lower edges of the panels above them.

For strength, stagger the bracing above and below each other — this makes fitting easier, too — but if they are to support the edges of two sheets of drywall they must all be in line. In this case, the center line of each brace must coincide with the edges of the panels. Mark the brace positions on the studs with a pencil and level to make sure they are all horizontal.

Cut the bracing so that it is a close fit between the studs but not over-length, otherwise it will push the studs out of true.

Begin fitting the bracing at the wall end of the partition and work in towards the center. A block of wood nailed to the wall stud will support the end of the first brace while you nail through the second stud into the other end of the brace. Use two nails. Then toe-nail the inner end of the brace to the wall stud. If the bracing is to be lined up, repeat this procedure for each one; if it is to be staggered, simply drive nails through the studs into the ends of the brace.

The ends of the bracing (“header”) over a doorway must be fitted in 1 1/2in deep slots cut in the sides of the adjacent studs. Cut down the side of each slot with a back saw and remove the waste with a lin bevel-edged chisel, working in from each end, or use a double stud at the header ends to support it.

Having completed the framework, you can remove the section of sole plate from the threshold of the doorway. Simply saw through each end level with the studs on each side. Then clad the framework with gypsum board, trimming the panels round the doorway flush with the studs and header.

The door opening should be trimmed with lengths of 4 x in planed softwood that fit flush with the faces of the gypsum board panels on each side. Cut a length to fit snugly between the studs at the top and screw this to the header. Then screw two longer pieces to the studs on each side of the door opening.

Finally, cut pieces of molding to fit round the door opening, mitering their corners at 45°. Nail the molding to the edges of the trimming pieces with in finishing nails, driving their heads below the surface.