Why should I use aircrete for my self-build project?

When it comes to creating a new home, the bits you don’t see can be just as important as the bits you do see. Getting the fabric of your house right is absolutely essential if you want it to perform well – and it pays to think about this element of your project right from the start.

What are the key considerations self-builders should take into account when deciding what structural materials to use in their projects?

Before deciding what building materials to use, self-builders and homeowners need to primarily think about timescales, budget, Building Regulations, aesthetics, planning regulations and how sustainable the they would like the house to be.

However, a lot comes down to preference – and masonry is the preferred house building route in the UK. The materials involved give homeowners a feeling of solidity and reliability that isn’t always possible to achieve with lightweight frame structures.

It is not unknown for homeowners to go around knocking walls with their fists – the idea behind this is to see how solid a wall is. This is important when it comes to common household tasks, such as fitting shelves and hanging heavy mirrors.

For self-builders, time is often of the essence. How long does it take to erect the shell of a house using masonry materials?

It can take as little as a couple of days to get the main structure up. Aircrete blocks, for example, are much lighter in weight than traditional dense concrete versions – meaning it is easier and quicker to manoeuvre them around site.

However, the real speed advantage comes when you consider the mortar and the size of the units. For instance, using large-format blocks such as H+H’s Jumbo Bloks and Multi Plate blocks means that you can get more wall up in one go. Multi Plates are over twice the size of a standard Celcon Block, helping to significantly speed up the build process.

We also have our own construction method, called Ra Build. This is a combination of large format blocks and the thin-joint construction system.

The term ‘thin-joint’ refers to the mortar thickness between the blocks. Using thin-joint blockwork enables walls to be built very quickly without having to wait the conventional 24 hours for the mortar to set before further loading can be applied. The reduced thickness of the mortar bed helps to ensure the structural shell is virtually airtight upon completion.

Ra Build enables the inner leaf of the external walls of a house to be built in a couple of days, totally independently of the outer leaf. This allows the first fix trades to begin their work before the walls are even complete, which saves both time and money.

Can a masonry home deliver on sustainability, thermal efficiency and air tightness?

Aircrete ticks many of the sustainability boxes for self-builders. At least 70 per cent of every H+H aircrete block is made of pulverised fuel ash – a waste material that is a by-product of energy generation that would otherwise go to landfill.  This type of aircrete can achieve high ratings in the BRE’s Green Guide to Specification.

Local sourcing is important, too – so it’s worth looking for products manufactured entirely in the UK from locally available materials. This not only means less air miles for the products you use on your project, but also helps contribute to the local economy around UK manufacturing bases.

The philosophy we recommend to self-builders is very much one of taking a fabric first approach – whereby energy efficiency is built into the structural fabric, so that the building performs well over its entire lifetime. Part L of the Building Regulations now reflects this kind of approach.

This is a far better route to an efficient, comfortable home than relying on bolt-on technologies that rely on the behaviour of the house’s occupants to achieve the desired effect.

How can I specify a masonry home?

A number of services are now available to combine the structural specification and materials supply side of a bespoke project. The great thing about this kind of package is that the self-builder gets everything they need, when they need it. The only thing left for the customer is to decide what the final finish will be.

For example, last year H+H launched a Masonry House Package with a view to specifically helping self-builders. It takes the hassle and worry out of the fundamental elements of a building project – namely the walls and foundations. The package includes technical advice, detailed product specification and the supply of the core masonry-related products required for the build.

Customers can send in their drawings for our technical team to assess. Working from these, our team will calculate the materials required to build the walls and foundations using Celcon Blocks and the thin-joint mortar system.

The Masonry House Package provides self-builders with a fixed price quotation for the supply of all the necessary structural materials to their site, including the Celcon blocks, Celfix thin-joint mortar and wall ties.

Cliff Fudge is technical director at H+H, a leading manufacturer of aircrete blocks and systems. He has been involved in the construction sector for over 30 years, focusing primarily on the development of aircrete building products.