What Superstructure To Use When Self Building?

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 or brick slips  can create the look of brick and block on a timber frame build.

Most of our client will lean towards and modern method of construction, the most popular being some sort of timber frame system.

Brick and block

Around 70% of new homes in the UK are brick and block, a ‘wet’ system of building, although this is down to 45-50% within the self build arena.

With this build system 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.

·        Thin-joint blockwork is a variation of brick and block, that uses just 3mm of mortar. It’s a specialised system that makes for a quick build. It has to be accurately built because it doesn’t use conventional 10mm mortar beds — hence the name, thin-joint.

Timber frame

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 or Timber to name a few.
However, the foundations must be perfect, and there’s little scope for serious modification once built.

SIPs – Structural Insulated Panels

A system that uses panels made of a sandwich of OSB (oriented strand board) 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.

ICF – Insulated Concrete Formwork

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.

‘Natural’ build materials

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 incorporatin at least some of these methods and materials increases.

Passive or Passivhaus

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.