Most British builders are used to building with masonry (or brick and block). However in Scotland, timber framed homes are generally the norm. Both systems are commonly employed by self builders, and brick slips or a brick skin can create the look of brick and block on a timber frame build.
Self builders are also keen innovators so they often explore alternative construction methods and materials. Their reasons will include the finished look, the eco credentials, the ease of manually handling the materials, the ability to source materials, and the availability of expertise and contractors. Budget may or may not be a factor.
Around 70% of new homes in the UK are brick and block, a ‘wet’ system of building. With this you have an inner skin of blockwork tied-in with an outer skin of brickwork.
Houses are physically built on site, meaning that this route has a longer ‘on-site’ build phase, which can cause inconvenience to neighbours or be liable to theft of vandalism. But it’s on-site approach means that it can be forgiving of discrepancies in foundations.
As the dominant system there are loads of firms and tradesmen familiar with it, and – with training – ambitious self-builders can also get stuck in.
However, as a wet system, it takes time to dry on site and is affected by bad weather. It also requires load-bearing walls, so open-plan designs need to be carefully planned.
The second-most popular route, built of wood products that act as the superstructure. This could be traditional post-and-beam, green oak, or modern interpretations, such as Glulam.
This is a specialist trade, built off-site in a factory to an agreed design, usually in a matter of weeks. Changes are costly once commissioned, and there’s little scope for self-builders to work on the actual structure.
As it’s prefabricated off-site, the frame is erected on-site in a matter of days, and the erection is all taken care of by your manufacturer and contractors.
Modern glued wood is enormously versatile, meaning it can create open-plan spaces and interesting designs with ease.
The outer skin can be finished in pretty much any cladding finish – brick slips to create the look of brick, render, timber or tile.
However, the foundations must be perfect, and there’s little scope for serious modification once built.
The Structural Timber Association has a list of audited members for you to choose from for your project, or visit the self build section on its website for a range of guides to help you with the decision making process, including:
A system that uses panels made of a sandwich of OSB (oriented strandboard) bonded around an insulated centre. These are precision made in a factory, making a quick on-site build, and the structure is quick to erect and needs very few load bearing walls.
SIPs can be used to make walls, floors, ceilings and the roof, and they maximise loft space as there’s no need for roof trusses. While a bit more costly than conventional timber frame, you save on labour costs.
The route also offers excellent air-tightness and high levels on insulation, but again this requires experienced tradesmen and precision engineering. Foundations have to be faultless, too.
The exterior can be finished in a choice of cladding finishes to create the look you want.
Like the famous building blocks kids play with, ICF is made of large hollow blocks that stack to create cavities that flow through the entire structure. Typically these are made of expanded polystyrene.
This insulated formwork is then pumped full of concrete to create a robust structure with great insulation values. Self-builders can easily get stuck-in with a bit of training from your supplier, but plans must be adhered to, as it’s very hard to change once the concrete is poured.
It’s a quick build system, but not that common and your foundations must be spot-on – mistakes are costly to remedy. Again a range of cladding finishes are available.
If a sustainable, eco-friendly, self build is important to you there are many other build routes with greener credentials. Some of the alternative construction methods include Hempcrete, green oak, cob, steel frame, straw bales, rammed earth and log building. Many are niche areas but each year the numbers of self builders incorporating at least some of these methods and materials increases. There are specialist lenders (Ecology Building Society) who will finance such schemes, and insurance companies (insurance Green) who cover the risks, and you’ll need contractors familiar with the materials and systems.
The informative presentation, ‘Modern Methods of Construction (MMC) & Eco-Building‘, explains the pros and cons of the main methods of construction.
Not so much a build route to the structure, building a passive house is about creating a home that’s got lower running costs due to the way its constructed. Consequently, attention is given to the orientation of windows to capture solar gain in summer with overhangs offering shading in the summer, as well as very high levels of insulation. They typically have mechanical heating and ventilation systems that circulate air throughout the house, reusing heat rather than venting it outside, and because of this they need to be extremely airtight.
You can find out more at the Passivhaus Trust.
There are hundreds of different companies and suppliers to the self build industry. The Self Build Directory offers a listing which you may find useful, or take a look at our CASE STUDIES to get a feel for how homes can be built in different ways
Build It’s got a useful guide: ‘Beginner’s guides: Structural options’[Build It]
‘House Construction Methods’ [The Self Build Guide]