Modern house with exposed blockwork prepared for external wall insulation and rendering in South Wales

Internal Wall Insulation in Llantrisant , Rhondda Cynon Taf

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07393 355531
Serving Llantrisant & Rhondda Cynon Taf

Expert Internal Wall Insulation in Llantrisant

Living in an older property in Llantrisant often means dealing with the charms of character features alongside the frustration of cold, damp walls. At Global Plastering, we specialise in internal wall insulation, providing a robust solution for homeowners across Rhondda Cynon Taf who want to improve their thermal comfort without altering their home’s exterior. Whether you reside in a classic Victorian terrace, a solid-wall semi-detached home, or a non-traditional build such as an Airey or Cornish unit, our team is here to help you create a warmer, more energy-efficient living space.

South Wales and South West England

07393 355531

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Our Trusted Partners & Brands

Freshly plastered and skimmed white walls in a modern dining room completed by Global Plastering in South Wales
PAS 2030 Accredited IWI Installers

Expert Internal Wall Insulation Across South Wales

Based in Ferndale, Global Plastering provides highly efficient internal wall insulation (IWI) for properties throughout a 60-mile radius, covering South Wales and South West England. From solid wall Victorian terraces to complex commercial retrofits, our PAS 2035 compliant solutions drastically reduce heat loss, lower soaring energy bills, and instantly improve your EPC rating.

Why choose IWI for your Rhondda Cynon Taf home

Many properties in our area suffer from significant heat loss through solid walls, which can lead to high energy bills and condensation issues. Internal wall insulation acts as a thermal blanket, significantly reducing the amount of heat escaping your home. By installing high-performance insulation boards directly to the inner surface of your exterior walls, we can drastically improve your property’s EPC rating and create a more consistent temperature in every room. It is the perfect choice for homes where external wall insulation is not possible, such as those in conservation areas or properties with protected stone facades.

Our professional installation and damp prevention process

Quality is at the heart of everything we do. Our installation process is fully compliant with PAS 2035 retrofit standards, ensuring your home is treated with the care and technical precision it requires. We begin with a thorough survey to assess the moisture profile of your walls, as effective damp prevention is critical when insulating from the inside. We install vapour control layers alongside premium insulation boards to prevent interstitial condensation. The final stage involves a professional plaster finish, leaving your walls smooth, level, and ready for you to paint or wallpaper immediately.

Can IWI help with condensation and cold rooms

If you are finding dark spots or mould growth on your internal walls, or if your rooms feel perpetually draughty despite the heating being on, insulation is often the answer. By raising the internal surface temperature of your walls, IWI stops the cold bridging effect that allows condensation to form. This not only makes your home feel more comfortable during the winter months in Llantrisant but also protects the structural integrity of your property against damp-related decay. We help landlords and homeowners alike meet modern efficiency standards, ensuring your investment is both healthy and warm.

Trust our local PAS accredited retrofit experts

As a company serving the South Wales and South West England region, we pride ourselves on our technical accreditations and our commitment to local property standards. We are fully PAS 2030 accredited and hold CHAS certification, giving you the assurance that your retrofit project is managed by qualified professionals. We also provide SWIGA insurance-backed guarantees, protecting your investment for the long term. If you are ready to stop heating the outdoors and start saving on your energy bills, our team is ready to assist. Contact us today at 07393 355531 to book your free survey and discuss your home insulation requirements.

Why Choose Global Plastering?

Your trusted, PAS-accredited experts in internal wall insulation, delivering outstanding energy efficiency and flawless finishes across Ferndale, South Wales, and the South West.

Local South Wales Experts

Based in Ferndale, we cover a 60-mile radius through to Bristol. We possess deep expertise in retrofitting Victorian, terraced, and solid wall properties.

Fully PAS 2030 Accredited

We are fully PAS 2030 compliant and CHAS registered. We provide comprehensive SWIGA insurance-backed guarantees for absolute peace of mind.

Flawless Plastered Finishes

Internal wall insulation involves careful dry-lining and skimming. As highly experienced plasterers, we ensure your newly insulated walls are impeccably smooth.

Lower Bills & Better EPC

Tackle soaring energy costs, draughts, and cold spots. Our tailored IWI solutions reduce heat loss and guarantee vital improvements to your property's EPC rating.

Internal wall insulation being installed with Mannok PIR boards between timber studs in a South Wales property.
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Plastering Services Across South Wales and South West England: 07393 355531

What Our Clients Say About Global Plastering

"Excellent work the team removing our old 1970's cladding and replacing it with insulation and a rendered finish. The job went smooth from start to finish with all old materials removed from site. We are very pleased with the end result and would thoroughly recommend Global Plastering."

A. Jenkins (Ferndale)

"Dilwyn and his team were brilliant and made a lovely job of our EWI. They were very friendly, hard-working, and left no mess at the end of each day. Our house looks great and we can definitely feel the benefits of the insulation already. I'm very glad we chose EWI especially with energy costs as they are now."

G. Toogood (Bristol)

"Charlotte and the team were professional, reliable, and excellent at communicating throughout. They did a fantastic job of skimming and rendering the back of our house during our renovation. Superb quality of work and highly recommended!"

M. Lewis (Cardiff)

FAQ

Frequently Asked Questions

Answers to common questions about our internal wall insulation services, heat loss solutions, and PAS 2030 compliant retrofits in South Wales and South West England.

How much space will I lose inside my rooms?

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This is a common concern for homeowners in Ferndale. Modern high-performance insulation boards are incredibly efficient, meaning we can achieve great thermal results with relatively thin materials. You will typically lose about 60mm to 100mm on the treated walls. Most customers find this small trade-off is well worth it for a home that is significantly warmer and cheaper to run.

Will IWI cause damp or condensation in my home?

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When installed correctly by experts like us, IWI actually helps reduce the risk of surface condensation. By warming up the internal surface of the wall, you remove the "cold spot" where moisture in the air usually settles. We use vapour control layers and ensure proper ventilation is maintained to keep your home healthy and breathable.

Can I still hang pictures and shelves on insulated walls?

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Yes, you certainly can. While you need to be mindful of the depth of the insulation, we can advise you on the best fixings to use. For heavy items like radiators or kitchen cupboards, we plan ahead and install "pattresses" or extra timber supports behind the boards during the installation process.

Is there a lot of mess during the installation?

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We won't sugar-coat it—any internal work involves some disruption. However, we pride ourselves on being respectful guests in your home. We cover flooring, protect your furniture, and clear away all debris. Because we are professional plasterers by trade, we ensure the finish is top-tier, leaving you with a blank canvas ready for paint.

Still have questions? Contact our South Wales and South West England Plastering experts today!

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Proudly Serving South Wales & South West England

Global Plastering are your trusted, PAS 2030 accredited insulation and rendering experts. Based in Ferndale, Wales, we cover a 60-mile radius, providing high-quality external wall insulation (EWI), internal wall insulation (IWI), and premium silicone rendering to reduce energy bills and transform cold houses. Explore our primary service areas below.

Our Key Service Areas

South Wales

  • Rhondda: Ferndale, Pontypridd, Porth
  • Cities: Cardiff, Swansea, Newport
  • Surrounding: Bridgend, Merthyr Tydfil
  • Specialists in upgrading terraced and solid wall homes
  • Experienced in Cornish and Airey non-traditional builds

South West England

  • Bristol and the M4 Corridor
  • Bath, Gloucester, and Cheltenham
  • North Somerset and surrounding borders
  • Expert rendering for Victorian and Edwardian properties
  • Commercial insulation and decarbonisation projects

PAS Accredited Experts

  • Fully PAS 2030 and PAS 2035 compliant
  • SWIGA insurance-backed guarantees provided
  • CHAS registered for commercial health & safety
  • Deep understanding of MEES compliance for HMOs

Book a Free Retrofit Survey

Contact Global Plastering today for a no-obligation quote on insulation, rendering, or plastering across Wales and the South West.

Call 07393 355531

If your specific location within our 60-mile radius isn't listed, please don't hesitate to get in touch. We cover all domestic, commercial, and landlord properties within this area.

Our Operating Radius & Coverage

Map shows our primary service areas across South Wales and South West England.

Book Your Free Internal Wall Insulation Survey Today!
Call South Wales and South West England's Trusted Plastering Experts on 07393 355531