Project Managing Your Own Build
Thinking of project managing your build? Peter Eade looks at the jobs you can tackle yourself, and the process of supplying materials to your contractors.
Dealing with subbies – and ordering materials
If you intend to manage your project using subcontract labour it is important to know the order in which the work will proceed. By employing individual trades it is probable that they will only be offering their labour and will rely on you to supply the correct quantities of materials on site at the right time.
Calculating quantities off the plans is relatively straightforward and accurate measuring will ensure that there are no delays due to material shortages.
Managing a project for the first time can be a daunting task but in reality it only consists of two stages: organising the labour force and having the right materials on site as and when they are required. Skilled tradespeople will not need too much management as they will know their job.
Buying the right materials at the right price needs to be dealt with in a professional way and this starts by accurately taking off the quantities from the plan. Once this is done quotations can be sought from the builders’ merchants and other suppliers. Ideally get in two or three quotes before placing any orders.
Plan well ahead when talking to the various trades.
This will avoid too many delays. Again, get quotations from each of the trades before engaging them.
A well-run site is far less stressful and if thought is given to each aspect of the project things should move forward quite smoothly.
Preparing the site will require general levelling and removal of all vegetation and turf from the area where the house is going to be built. Most of the site preparation can be carried out by someone with practical skills. A mini digger with a front dozer blade is probably the easiest way of clearing the site. This can also be used to prepare trenches for the water and electricity services.
Setting out must be done accurately and time should be given to avoid ending up with a house that is built to the wrong measurements or possibly out of square.
The groundwork is best undertaken by experienced groundworkers. They will provide all of the labour but will expect the materials to be on site as and when they are required.
These will include ready-mixed concrete, bricks/blocks to build up to ground level and then face bricks from just below ground level up to damp-proof course. They will also require pipes and fittings for any drains which run within the house, crushed hardcore, and concrete will be needed for the over-site flooring. If the latter is block and beams these will also need to be supplied.
For a typical 600mm x 225mm strip foundation one cubic metre of concrete will lay around seven linear metres. Wall ties for the bricks and blocks and DPC will also be required. The quantity of crushed hardcore – if laid to a depth of approximately 150mm – will mean one cubic metre will cover approximately six square metres.
The damp-proof membrane (DPM) is sold by the roll and if under-slab thermal insulation is required it is bought by the square metre. One cubic metre of ready-mixed concrete laid to a depth of 125mm will cover eight square metres of floor.
The external drainage should also be dealt with by the groundworkers but is best left until the house is almost built. This avoids having open trenches and the possibility of drains being damaged. All drainage supplies are bought individually.
Bricklaying is a skill which cannot be learned in five minutes and is best left to professional bricklayers.
Quantifying the bricks and blocks required is quite straightforward though. There are 60 bricks to a square metre (if it’s stretcher bond) and 10 internal blocks. Wall ties are spaced at 900mm horizontally and 450mm vertically and cavity insulation is supplied by the square metre. Lintels are bought to the length required, lintel weep vents are bought individually, cavity closers come by the metre and DPC by the roll. Sand is best ordered by the truckload and cement by the tonne. When the scaffolding is required this must be erected by a specialist company. Should any alterations be needed as the work proceeds the changes must also be dealt with by the scaffolding firm.
Carpentry comes in two stages – first and second fix. First fix is the floor and ceiling joists, and roof timbers (the roof can be either a traditional cut or roof trusses).
Once the roof is on and waterproof the window boards and door linings are also fixed. It is at this point the staircase should be installed making sure it is well protected to avoid damage. When ordering any structural timber check what grade is shown on the Building Regulations approved plans and order to the nearest length.
Timber for joists, stud work and rafters comes in the following standard lengths: 1.80m, 2.10m, 2.40m, 2.70m, 3.0m, 3.30m, 3.60m, 3.90m. 4.20m, 4.50m, 4.80m, 5.10m. 5.40m, 5.70m, 6.0m and 6.30m.
Carpentry is a skill but to a certain degree some of the work can be undertaken by unskilled labour.
Cutting in floor joists and bedding on roof plates is quite straightforward but cutting in the roof and fitting fascia boards and soffits are definitely jobs for professionals.
The second fix involves installing floorboards, architraves, skirtings and hanging doors. Apart from the flooring and decking all other second-fix carpentry happens after the plastering is finished. Second-fix carpentry can possibly be done by someone with practical skills but the job may take a lot longer.
Roofing includes fitting the roofing membrane to the rafters, fixing battens, laying the roof tiles and cementing on the ridges, hips and verges. If standard plain tiles are to be used there are 60 to the square metre. Concrete interlocking tiles and slates come in various sizes and the quantity per metre needs to be checked with the manufacturers.
The roof fittings are ridge tiles, valley tiles, hip tiles, tile-and-halfs and verge under cloak – all of which are bought individually or by the metre. Although anyone with a bit of practical skill can lay tiles neatness is required to bed on the hips and verges and the job is perhaps best left to a skilled roofer.
Gutters and downpipes
Before the scaffolding is removed the gutters and downpipes need to be fixed. All gutters and downpipes are supplied by the length and fittings are sold individually. By using the gutter supplier’s catalogue it is easy to work out what is required. Fitting gutters and downpipes can be carried out by anyone with practical skills but gutters need to be fixed to levels and downpipes plumb.
The window openings should be measured by the supplier. This avoids mistakes which can be expensive. Just before the scaffold is removed the upper windows need to be fitted – the ground-floor ones are best left until the scaffolding is removed. Fitting the windows and glass is probably best left to the window suppliers or a qualified installer.
Insulation and sound proofing
Placing insulation between ceiling joists and sound proofing to floors, joists and to stud walls is a semi-skilled job and with care can be dealt with by anyone with a bit of practical skill. Thermal insulation is ordered by the roll and rigid insulation by the square metre. Mineral wool acoustic insulation is sold by the roll.
Neat and smooth plastering to the walls and ceilings is very important and the work is best left to an experienced plasterer.
Fixing plaster board to the ceilings is a job that can be carried out by anyone with a bit of practical skill.
If the walls are to be dot-and-dab plasterboard this job too can be undertaken by semi-skilled labour.
Calculating how many boards are required is quite straightforward: just measure how many square metres are required and place the order. Don’t forget the dry-wall screws for fixing. Before ordering bags of plaster, angle beads and scrim, check with the plasterer on the quantities required.
Plastering itself is best left to the experts. Plaster needs to be applied quickly before it goes off.
Plumbing, heating and electrical work
Unlike other trades, plumbers and electricians usually supply their own materials. To get competitive quotations heating, plumbing and wiring schedules need to be prepared. The plumbing and heating schedules will show the positions of the boiler, radiators and sanitaryware while the electrical schedule shows the positions of all lighting and switches, together with sockets and all other items requiring an electrical supply.
Some of the plumbing and heating can be done by someone with practical skills but all the work needs to be checked by a professional who can also install the boiler. The electrical installation should be left to a qualified electrician.
Both the electrical installation and plumbing/heating work come as first and second fixing. The first fix is done before the plastering is completed and the second fix is done prior to any decorating.
Kitchen units are best installed by an experienced fitter, although someone with the right tools and practical skills should be able to achieve a reasonable finish.
Wall and floor tiles
Wall and floor tiles are bought by the square metre, although many suppliers these days like to sell them priced individually. In addition to the tiles, spacers, adhesive and grout are also required; the tile suppliers should be able to advise on the quantities needed.
Tiling is undoubtedly a skill but it can be undertaken by a practical person – it will just take much longer to produce quality work.
Of all the trades required to build a house decorating seems to be the one job that everyone thinks they can do. It matters not who does the work but skill is required in both the preparation and application of the paint if a professional finish is to be achieved.
It is well worth considering employing an experienced painter if you are new to decorating.