The cost of a loft conversion will depend on many factors such as size, accessibility and fittings. A small loft conversion will probably cost about £15,000 for one room in the roof and the amount of work will include reinforcing the floor, adding skylights and dormer windows, adding extra insulation, providing stairway access to the room, extending the electrical circuit, adding central heating and any plumbing facilities such as en-suite shower room or WC. The project will also have to comply with any Fire Regulations that may apply through the Building Regulations. Don’t forget to find out how much loft conversion plans cost as an architect will have to draw these.
Having a loft conversion built into your house is probably one of the cheapest ways to produce more living space within the average home. The work is being done within its existing footprint so there are no problems with digging and laying foundations, incorporating damp-proof membranes and building supporting walls. How much easier is it to just use the space inside the existing roof and add a few more structural timbers and a window or two? This article will explain the basics of how to go about building a loft extension bedroom.
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Types of Loft Conversions
There are four different types of loft conversion that the average homeowner can choose from.
- Dormer Loft Conversions. This is probably the loft conversion that is most commonly fitted in standard homes for the simple reason that they are basically just an extension of the existing roof and dormer extension costs are very much cheaper than a full roof conversion cost. A dormer loft conversion also allows the roof room to have vertical walls with a horizontal ceiling, unlike other loft extensions that may have sloped walls. These are really versatile and can be built onto just about any type of building, from a semi-detached, a terraced, a detached house, or a bungalow. These also usually allow for the new staircase to be fitted directly above the existing one.
- Hip to Gable Conversions. These are usually built onto semi-detached, detached or end of terrace homes. They are a way of providing more space in the roof of a home with three or more sloping roof planes. Basically, the hipped roof is built up to convert it into a gable ended roof. The building materials used will definitely need to match with the existing materials and Planning Permission will probably be required.
- Mansard Loft Conversion. This method generally requires the most alteration work to the property and will definitely need Planning Permission due to the alteration in the roof profile and the extra structural timbers needed. The Mansard style generally has a flat roof with outside walls angled backwards at an angle of 72 degrees due to a planning criterion which specifies 72 degrees as being a roof rather than a wall.
- Shell Loft Conversion. This is also sometimes known as a ‘first fix loft conversion’. It is an ideal way for the homeowner to do a bit of DIY or employ a local handyman without having to worry about the skills involved in keeping the house weathertight. A specialist company produces a waterproof shell in compliance with the Building Regulations and any necessary Planning Permission, complete with staircase, structural floor joists, floors and dormer windows while leaving the homeowner to sort out all the little details inside.
Types of Tradesmen
The types of tradesmen needed to build and complete a loft extension will depend on your budget and how handy you are with DIY. You will always need a project manager whose job is to organise the labour force and deliveries of materials. He will also negotiate with local builders merchants to get the best material prices and dormer window costs. He will liaise with the local Planning and Building Regulations offices, enquire about loft extension costs and loft conversion quotes from various tradesmen. To actually do the work will require many trades including an architect, structural engineer, carpenter, roofer, bricklayer, plasterer, plumber, electrician and labourers. In practice, however, the following are needed to complete everything.
- A specialist loft conversion company. This company will do literally everything for you. They will organize the survey, get plans drawn up, organise planning permission if necessary, do all the work and hand over a completed structure ready for you to install your furniture. They will even paint the walls if necessary.
- A general builder. With this type of contractor, the clue is in the name. They will usually be a small local company with a few full-time staff; usually a carpenter, bricklayer and labourer. They will often subcontract additional work to roofers, electricians, plumbers and glaziers. Often they will also sort out architect’s plans and planning permission applications too. Most general builders will be able to give a full loft conversion price to incorporate everything.
- You can project manage the work yourself; handle the planning inspector; supervise tradesmen and organise deliveries but we wouldn’t advise this if you don’t know what you are doing. It is very easy to be taken for a ride by unscrupulous tradesmen and very easy to lose lots of money.
How long a loft conversion takes to build
Once again, the amount of time taken will depend on what you have done. On average the majority of builders would probably say it takes about six weeks to get one finished, but this wouldn’t take into account contacting the planning office, building regulations office or having plans drawn up. It also would depend on whether the tradesmen are available to do their particular jobs on time and will not include any holdups with deliveries of materials. So really as you can see, this question cannot be answered properly with any degree of accuracy so don’t insist on the builder giving you a definite timeframe.
How to get planning permission in the UK
In the UK you don’t normally need to apply for planning permission for a standard loft conversion or dormer unless:
- The new work is over 50m2 or 40m2 if you are converting a terraced house (this includes other extensions that may have been built previously).
- The extension protrudes past the plane of the existing front elevation roof slope.
- The extension is higher than the existing maximum height of the roof.
- You wish to include clear glazed side windows (in the gable end), less than 1.7m above the roof room floor.
- Your home is listed or you live in a designated conservation area or similar.
- The dormer is within 200mm of the eaves.
It is always worth checking these points above with your local planning department because the regulations may have changed since the time of writing of this article. They will also help and advise if you are unsure. Even if your project doesn’t need Planning Permission it will require Building Regulations Approval and you should contact the Building Regulations Inspector before starting the project.