Internal wall insulation in Four Oaks.

What are Four Oaks houses usually like?

Four Oaks sits beside Sutton Park, and much of it is made up of larger detached and semi-detached houses: Edwardian homes, interwar houses and later infill on generous plots. Many have two-storey bays, high ceilings, picture rails, cornices and deep skirtings.

Those features are part of why people buy here. They also mean the walls are bigger and the details more delicate, so internal insulation has to be planned around them rather than over them.

Does a high ceiling change the price?

It can. Pricing starts from about £2,300 per wall, but a tall wall with a bay, two windows and a cornice is a bigger job than a plain wall in a small bedroom. As a guide, PIR is usually £2,300 to £3,000 per wall over three to four days, and a breathable wood fibre and lime system is around £3,000 and about five days on a typical wall.

For larger rooms, I measure on the visit and price each wall in the written quotation, so you can see exactly where the cost goes. The internal wall insulation cost guide explains what moves the price up or down.

Can you keep the cornices, picture rails and skirtings?

Usually, yes, with planning. Insulation goes on the wall, not the ceiling, so a cornice can normally stay. The new wall face finishes neatly beneath it, and the joint is made good by hand.

• Cornices: left in place, with the insulation stopped just below and the line made good.
• Picture rails and skirtings: carefully removed, stored and refitted on the new wall face where possible.
• Window reveals and boards: insulated and finished, often with deeper boards to suit the new thickness.

Where original lime plaster is present, I often finish in lime too. The lime plastering service and the lime versus gypsum guide explain why.

Our two-storey bay is the coldest part of the house. What can be done?

Large bays have a lot of glass and a lot of edge, and on many houses of this era the panels under the windows are thinner than the main walls. Both floors of the bay usually need the same treatment, so I look at them together.

Bay insulation starts from about £2,300 for a single bay. The bay window insulation service covers the method, and the cold bay window guide explains what is usually going on behind the plaster.

We are thinking about a heat pump. Should we insulate first?

It usually makes sense to reduce heat loss first. Heat pumps run best at lower flow temperatures, and a house that loses less heat needs a smaller system and smaller radiators to stay comfortable. Cold solid walls are often the biggest single loss in an older Four Oaks house.

As a Domestic Energy Assessor and Retrofit Assessor, I can help you think about the order of works. I do not install heating, but I can tell you which walls are worth insulating before a heating engineer sizes the system.

Do I need permission to insulate inside a Four Oaks house?

Internal insulation does not normally need planning permission, because the outside of the house stays the same. Listed buildings need listed building consent for internal work, and some roads in Sutton Coldfield are conservation areas or have their own restrictions. If anything like that applies to your house, I will flag it at the visit so you can check with the council.

Do you cover Four Oaks and nearby?

Yes. Four Oaks is usually 20 to 25 minutes from Bloxwich. I work across Sutton Coldfield, plus Streetly, Erdington and Lichfield. My main internal wall insulation page for Sutton Coldfield covers the service in full.