Replace a conservatory with an oak framed room

What does replacing a conservatory with oak involve?

A new room, not a roof swap. The conservatory comes down and a heated oak framed room goes up in its place.

It costs the same as building an extension of that size: £2,500 to £5,000 per m² including VAT, designed and built. If the conservatory's base is sound, keeping it saves £15,000 to £25,000. We check that on the first visit. Built within 90 minutes of Abergavenny.

How much does it cost to change a conservatory into an extension?

The same as an extension of that size.

Lean-to roof, per m² including VAT

• 20 to 29 m²: £3,400–£4,300
• 30 to 60 m²: £2,500–£3,550

Gable roof, per m² including VAT

• 20 to 29 m²: £3,750–£4,500
• 30 to 60 m²: £2,900–£3,850

Most conservatories are 12 to 25 m², so the typical job is a lean-to in the 20 to 29 m² band; under 20 m² we quote per job. If the base and dwarf walls are sound and sit on proper footings, we build on them and the saving is £15,000 to £25,000. If they're not, we take them out and start again, and you'll know which on the first visit, before anything is priced. Correct at October 2026.

What's in the price

• Taking down and removing the conservatory
• Design, the planning check or application, building regs drawings, our engineer
• New footings and slab, or building on the sound base
• The oak frame, roof structure and covering
• Glazing and doors to your design
• Walls insulated, lined, skimmed and decorated
• Electrics, heating tied into the house, the opening made good

Quoted on top

• Floor finishes, kitchens, underfloor heating
• Terraces, steps and landscaping
• The council's fees

Can I replace a conservatory without planning permission?

Usually, if the new room sits on the same footprint and is single storey.

It also has to stay within the permitted development limits for your house. The limits differ between Wales and England and fall away in conservation areas and on listed houses. We check before drawing. What always applies is building regulations: a conservatory was exempt from them, an insulated room isn't, and our drawings and the inspection are in the price.

Why not just replace the conservatory roof?

If the conservatory is sound and the roof is the only problem, do that instead; it's not work we do.

A solid roof on a uPVC conservatory fixes the heat and the glare, and it's a fraction of the price. It doesn't fix the frame, the single-skin walls or the feeling of sitting in a lean-to. If you want a room that's warm, quiet and part of the house, this page is the answer.

What happens to the old conservatory?

On a design and build job we usually take it down and away at the start of the job, and that's in the price.

The opening into the house is boarded up until the new room is closed in.

Which conservatories have we replaced?

Each one has its own page, with the photographs and the story of the job.

Oak frame extension at Ty Fry: Crickhowell, Powys, 2022. Designed and built: two metal-frame conservatories came off and one oak frame went on.

Oak frame extension at Pontypool: Pontypool, Monmouthshire, 2023. Designed and built: a cold conservatory replaced with a smaller oak room used all year, and a covered outdoor area to match.

More of our work: see every project.

What should you read next?

• Do you need planning permission for an oak frame extension or garden room?
• How much does an oak frame extension cost?