Two-storey extensions in Merthyr Tydfil
Need more room in Merthyr Tydfil? Two-storey and first-floor extensions add bedrooms and living space without moving. Here's everything we offer locally.
Merthyr Tydfil at a glance
- Postcode districts
- CF47 and CF48
- Area
- Mid Glamorgan, Wales
- Price region
- Wales
- Nearest towns
- Abercanaid (1.8 miles), Aberdare (3.8 miles), Rhymney (4 miles), Mountain Ash (4.4 miles)
- Distance to Rhondda
- about 6.9 miles
- Approvals
- Two-storey rear: ground floor up to 4 m, first floor up to 3 m and 10.5 m from the rear boundary. Some two-storey side extensions can be permitted development.
We cover postcode districts CF47 and CF48 in and around Merthyr Tydfil, along with neighbouring Abercanaid, Aberdare and Rhymney.
Extensions available in Merthyr Tydfil

Two-storey rear extensions
Guide from £51,500 in Merthyr Tydfil, including VAT.
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Two-storey side extensions
For homes in Merthyr Tydfil: typical guide from £79,000.
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Two-storey wraparound extensions
Guide from £111,000 in Merthyr Tydfil, including VAT.
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Part single, part two-storey extensions
Design, approvals and build for Merthyr Tydfil homes. Guide from £66,000.
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Extensions over a garage
Guide from £29,000 in Merthyr Tydfil, including VAT.
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First-floor extensions
Our Wales guide starts at £23,000 for this type.
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Two-storey extensions for semi-detached houses
Merthyr Tydfil guide price from £51,500, Standard spec.
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Two-storey extensions for detached houses
Our Wales guide starts at £79,000 for this type.
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Kitchen extensions with bedrooms above
For homes in Merthyr Tydfil: typical guide from £51,500 (before kitchen units).
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Extra bedroom and en-suite extensions
Our Wales guide starts at £51,500 (plus en-suite) for this type.
Learn moreWhich type suits your house?
Which type suits your house in Merthyr Tydfil depends mostly on where you have room. A deep garden points to a rear extension; space beside the house points to a side or over-garage extension; a house that already has a single-storey extension can often take a first floor on top.
Also available in Mid Glamorgan
- Two-storey front extensions
- Two-storey extensions for end-of-terrace houses
- Two-storey annexe extensions
- Garage conversions with a room above
- Two-storey extension plans and drawings
- Planning permission for two-storey extensions
- Structural engineering for two-storey extensions
- Building regulations for two-storey extensions
- Party wall notices for extensions
- Design and build two-storey extensions
Rules for Merthyr Tydfil
Merthyr Tydfil is in Wales. Two-storey rear: ground floor up to 4 m, first floor up to 3 m and 10.5 m from the rear boundary. Some two-storey side extensions can be permitted development. Householder planning application: £585. Councils normally decide householder applications within 8 weeks.
The full Wales rules explained
Questions about extensions in Merthyr Tydfil
Do you cover Merthyr Tydfil?
Yes. We cover Merthyr Tydfil (CF47 and CF48) and the surrounding area, including Abercanaid and Aberdare. The first site visit is free.
What does a two-storey extension cost in Merthyr Tydfil?
Using our Wales guide, a two-storey rear extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) is about £51,500–£69,500 including VAT. An extension over a garage is about £29,000–£42,000.
Which other places near Merthyr Tydfil do you cover?
Everywhere around it, including Abercanaid (1.8 miles), Aberdare (3.8 miles) and Rhymney (4 miles), and the rest of Mid Glamorgan.