Internal wall insulation in Streetly.

What kind of homes does Streetly have?

Streetly is mostly twentieth-century housing. There are interwar semis and detached houses, many with bay windows, and a lot of houses from the 1950s and 1960s, plus later infill. It is a settled area: many people have lived in the same house for years and extended it along the way.

• 1930s semis and detached houses: solid walls or early cavity, bays that are often lightweight panels.
• Post-war houses: usually cavity walls, where cavity fill may be the better first step.
• Extended houses: an old wall and a newer extension side by side, often with very different performance.

Because the age range is wide, I never assume. The visit tells me which category your house is in.

How do you plan a detached house in stages?

I look at the whole house once, then split it into sensible stages. Each stage is a room or a pair of rooms, priced separately, so you can do one this year and the next one later.

The order changes with your house and your habits. The room by room guide for 1930s semis works for most Streetly detached houses too, with an extra wall in each room.

My extension is warm but the old part is cold. Why?

Because the extension was built to modern standards, with insulated cavities, and the original house was not. The joint between them is often where condensation collects: the old wall is cold, the new room is warm and moist air settles on the cold side.

Insulating the original outside walls in the rooms next to the extension evens the temperatures out. Where the two meet, I take care with the junction so a cold strip is not left behind. If one bedroom stands out, the guide to one bedroom colder than the rest explains how I track down the cause.

What about the bay windows on Streetly semis?

Many interwar bays have a lightweight panel under and beside the window: timber framing with tiles outside and a thin lining inside. It looks like a solid wall but performs far worse. Bays on post-war houses vary more, so I check before quoting.

Insulating a bay usually costs from about £2,300 and is a small, contained job. The bay window insulation service explains how it is done, and the case study shows a bay bedroom where the wall surface went from 14.5°C to 18.4°C.

Our house backs onto trees and the back wall stays damp. Is that a problem?

It can be. Walls that get little sun dry out slowly after rain, and a wall that stays damp is a colder wall. Before insulating, I check the outside: gutters, downpipes, pointing and ground levels. Any water getting in has to be dealt with first.

On a wall like this, a breathable system of wood fibre and lime, around £3,000 per wall and about five days, is usually the safer choice because it lets the wall keep drying. Moisture modelling confirms it before the work starts. The lime versus gypsum guide explains why.

Does being close to your base make a difference?

In practical ways, yes. Streetly is 15 to 20 minutes from Bloxwich, so survey times are flexible and I am nearby if anything needs looking at after the job. Every customer gets a follow-up call about four weeks after handover anyway.

I also work in nearby Aldridge, Four Oaks, Kingstanding and the rest of Walsall. If you need a room replastered rather than insulated, see my plastering in Sutton Coldfield page.