Glass box extensions across Middlesbrough
A glass extension in Middlesbrough starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in MiddlesbroughFrom £28,000 inc VAT
- PlanningSame limits as single-storey rear; glazing checked for building regs
- Build time10–16 weeks on site
- Postcode districtsTS1, TS2, TS3, TS4, TS5

Guide prices for Middlesbrough
Labour and material costs vary across the UK, so for Middlesbrough we use our Yorkshire and the Humber factor (×0.94). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Middlesbrough: £2,820 to £5,450 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2 m × 4 m 8 m² | £28,000 – £34,000 | £28,000 – £35,500 | £32,000 – £44,000 |
| 3 m × 4 m 12 m² | £33,500 – £41,000 | £39,000 – £50,000 | £48,500 – £65,500 |
| 3 m × 6 m 18 m² | £50,500 – £61,000 | £59,000 – £74,500 | £72,500 – £98,500 |
Want a range for your exact size? The guide-price tool takes about a minute.
Planning and approvals in Middlesbrough
In England a glazed or orangery-style extension follows the same size limits as any single-storey rear extension: 3 m or 4 m without an application, or up to 6 m and 8 m through prior approval. Building regulations limit glazing to about a quarter of the new floor area plus the openings it replaces, unless whole-house calculations show the design still performs.
The planning position for a specific Middlesbrough address depends on its history and any designations, which is why we check it at the first visit.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Who a glass extension suits
- Garden-facing dining rooms
- Small infill spaces and side returns
- Period and listed-style houses where a light touch is wanted
Working in Middlesbrough
Across TS1, TS2, TS3, TS4, TS5, TS6, we can visit, measure and advise. We also work in nearby Redcar (8 miles), Northallerton (19 miles), Whitby (22 miles), Ripon (32 miles).
Billingham, in County Durham, is roughly 2 miles from Middlesbrough and also on our list. Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions people ask about glass extensions
Will my neighbours in Middlesbrough be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Who do I contract with for a glass extension in Middlesbrough?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
How long does a glass extension take to build in Middlesbrough?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 8–14 weeks design and approvals.
Are glass extensions cold in winter?
Modern double or triple glazing with warm-edge spacers and underfloor heating keeps them comfortable. They are not as warm as a solid room, and we explain the trade-off honestly.
How much does a glass extension cost?
Our guide range is about £2,820 to £5,450 per m² including VAT, because structural glass is made to order. A 12 m² standard-spec glass extension is typically £39,000 to £50,000 in Middlesbrough.
Book a free site visit in Middlesbrough
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.