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Land and housing development in Rhondda Cynon Taf
From our base in Mountain Ash, we take plots across the Cynon, Rhondda and Taff Ely valleys from bare ground to finished homes.
Developing land in Rhondda Cynon Taf
Rhondda Cynon Taf is home. C&M Developments is a trading name of C&M Jones Groundworks Limited, based in Mountain Ash, and we take land from bare plot to finished homes for landowners, housing associations, councils and investors across the county borough.
Because the groundworks team is our own, the drainage, foundations, retaining structures and reinforced concrete that decide whether a valley site is viable are handled by people with more than 50 years combined experience, not passed down a chain of subcontractors. You deal with one company from the first site visit to the day the homes are finished.
Our own groundworks team, C&M Jones Groundworks, works out of Mountain Ash in the Cynon Valley.
What it takes to build on a Rhondda Cynon Taf hillside
Most of the county borough is steep. Terraced streets climb the sides of the Rhondda Fawr, the Rhondda Fach and the Cynon Valley, and the flatter land on the valley floors is usually built on already or sits close to a river. A plot that looks simple on a map often needs cut and fill, a retaining wall on at least one boundary, and real thought about how a new home will be reached from the road.
The ground has a history too. Rhondda Cynon Taf lies on the South Wales Coalfield, and where a site falls inside a Development High Risk Area, most planning applications need a Coal Mining Risk Assessment. Disused tips are a live issue here: the Tylorstown landslip on the Llanwonno hillside followed Storm Dennis in February 2020, and Wales has since passed the Disused Mine and Quarry Tips (Wales) Act 2025.
Water shapes schemes as well. Storm Dennis flooded more than 1,000 properties across the county borough, 650 of them in Pontypridd. A new development of more than one home, or with 100 square metres or more of construction, needs sustainable drainage approved by Rhondda Cynon Taf County Borough Council, acting as the SuDS Approval Body, before work starts. For land near the Taff, the Rhondda or the Cynon, the Natural Resources Wales Flood Map for Planning under TAN 15 sets how the site is assessed.
Planning decisions rest on the council's Local Development Plan, adopted in 2011, which a Revised LDP for 2022 to 2037 will replace. Being local to all of this is useful. We can walk a site in Aberdare, Treorchy or Llantrisant, look at the slope, the access and where the surface water will go, and tell you plainly what the groundworks involve before you commit to a layout.
From the first site walk to the keys
- 1Get in touch and walk the site
- 2Prove the ground
- 3Get it out of the ground
- 4Build
- 5Hand over
Questions about Rhondda Cynon Taf
Yes. We are based in Mountain Ash in the Cynon Valley, so Aberdare, Pontypridd, the Rhondda valleys and Llantrisant are all close to home. We take on plots for landowners, housing associations, councils and investors throughout the county borough.
The county borough lies on the South Wales Coalfield. If your plot falls within a Development High Risk Area, most planning applications need a Coal Mining Risk Assessment. That can mean investigating for shallow workings before the foundations are designed, which we account for early.
Rhondda Cynon Taf County Borough Council, acting as the SuDS Approval Body. Since January 2019, new developments in Wales of more than one home, or with 100 square metres or more of construction, have needed sustainable drainage approved before work starts.
Get in touch
Got land, or a scheme that needs delivering? Tell us about the site and we will arrange a call, then meet you there to walk it together.
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