How we built our extension

Updated: Mar 20, 2018

Flora and Alex, Roath

When the couple planned their extension, it was to create more room for their growing family. Building on a budget came with challenges, but the end design is one that prioritises sustainability and has created a beautiful space for the family to relax and spend time in.

Here we share more and ask Flora about the experience.

What qualities matter to you in a home?

Natural light, a feeling of spaciousness and calm. Sustainability and working with the seasons.

Tell me about the house you live in

It’s a Victorian house dating from 1903. It was a typical Cardiff house in Roath with three bedrooms, built of stone with Bath stone trimmings. We chose it when we moved to Cardiff in 1996. We were relocating with a small child and needed somewhere fast! It was in the catchment of good schools and near the park. Now, we live in this nice, quiet, tree-lined street where children play out and there’s a real sense of community.

Local street party celebrating the Jubilee

What made you want an extension?

Our family was growing and the house needed refurbishing. We had a nasty PVC conservatory in need of attention.

Who helped you through the process?

I received advice from a lot of architect friends, and am an architect myself. We chose local builders. I asked a local cabinetmaker to remake the wooden ball on the stair post.

What went well?

We’re really happy with the design. The structure is a very minimal steel frame designed by an engineer from Arup. The outside walls are very thin because they’re made with a rain-screen cladding. This means we were able to maximise the interior space. The extension was very cheap – it cost about £2,500 per square metre and about £60,000 in all. We now have a lovely bedroom looking out onto a tree which is filled with sunlight.

View from the bedroom

Were there any difficulties?

We worked with a local builder but the relationship went a bit sour. When it’s a small job, builders can sometimes leave it to the last minute when they have a bigger job. Progress became ridiculously slow while we were paying to stay at a friend’s house. The builders cut costs on unhelpful things and made a lot of errors.

How is your extension sustainable?

We took what’s known as a fabric-first approach, which is about how you orientate the building and windows. When the tree outside is in leaf, it stops the house overheating by shading the large south-facing windows. In the winter, the leaves fall from the tree, allowing much needed sunlight into the building. The ground floor is made of tiled concrete, so that it will absorb heat from the sun and let it back out into the atmosphere at night-time.

The building’s also designed to benefit from a ‘stack’ effect. If the weather gets very hot, you can open up a window in the roof and the breeze will blow the heat through the building and out through the roof.

There are some things we wanted to do, but couldn’t. We wanted to have solar panels, but we didn’t have space for a storage tank. Instead we buy energy from Ecotricity. We wanted to make a shed out of local brick, but we couldn’t find any. We also explored using lime renders on the rain-screen cladding because it’s a more environmentally sustainable material, but this treatment was beyond our builder.

Exterior viewed from the garden

How do you feel about your home now?

We really love our house because we’ve had so many happy times here. Victorian houses do need a lot of tender, loving care though. Being a detached house with solid walls, we suffer badly from damp and condensation. Our extension however in nice and warm and dry.

Extended living room

Is there anything you learnt from the process?

I wish we had insulated the solid walls of the old part of our home where possible to prevent mildew and damp. Next time I would take more care with the choice of builder, but it’s always going to be hard to find builders who are prepared to try out vaguely unusual forms of construction.

What would you recommend to anyone in Cardiff looking to extend their home?

A good builder is worth the wait, as is paying over the odds to get someone you trust. Always use an architect and make sure they’re properly qualified. They will make the best use of space and save you money – they’re also much more knowledgeable about sustainability.

Have you or do you know anyone who has extended, redecorated or built a home in Cardiff or South Wales? We would love to feature your work. If so, get in touch here.