Basement Conversions
At Home Energy Save GB, we assess basement environments and implement compliant waterproofing and ventilation solutions in line with British Standards, ensuring a dry, healthy and usable living space long-term.
WHY CHOOSE US?
When it comes to basement damp and structural waterproofing, trust Home Energy Save GB to accurately diagnose the issue and provide effective, long-term solutions backed by decades of industry experience.
- Experienced & Qualified Local Surveyors
- 40+ Years Experience
- KIWA Accredited
- 5 Star Google Reviews
- 25 Year Guarantee On All Services
Book your FREE Comprehensive Damp Survey now or call us on 0800 065 4044 to take the first step towards a drier and healthier home.
Book Your FREE Survey Here
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Customer Reviews
EXCELLENT Based on 1723 reviews Posted on Tom OgdenTrustindex verifies that the original source of the review is Google. Eiick, was absolutely brilliant! Very experienced and diagnosed the problem immediately. Repair organised.Posted on Francisca CTrustindex verifies that the original source of the review is Google. Larry came around , gave a thorough explanation of how to sort out the loft and improve my energy efficiency.He was very professional and arrived on time.Posted on carl athertonTrustindex verifies that the original source of the review is Google. Alex and ben Arrived half an hour early. Walked me round everything that they was going to do. They then set about doing the tasks with complete professionalism. When they had finished they showed me everything that was done. They left the place clean and tidy. Highly recommendPosted on Becky CheadleTrustindex verifies that the original source of the review is Google. Brilliant service,even helped me move a bed🙂Posted on Georgie AlexanderTrustindex verifies that the original source of the review is Google. We had our survey done, by Phil. He was very knowledgeable in the field, and walked us through the solutions we need to take. Our treatment was carried out by Craig, who took special care of all household items, whilst carrying out the treatment. Craig made sure to explain the best methods of cleaning the treatment. Would highly recommend! Thank youPosted on Leah Warner-TedaldiTrustindex verifies that the original source of the review is Google. We had Kai and Sam come to do isotherm insulation on our walls. They were great, really upbeat and friendly. They worked really hard and left the place so tidy. The work looks good so far! Review is done on the day of completion Update: we had a lot of trouble with this company in the end. The plastering work ended up needing to be redone. It took 6 weeks for it to be redone and we were left with a completely unusable room and really bad communication. There were so many times when I rang through to the switchboard and escalated matters for nothing to happen. We felt totally helpless and stranded. I have since tried to get through to their complaints team to no avail. We had the isotherm sheeting fixed which was then skimmed over the top. Once this had set you could quite easily push it in with your finger, denting it (see pic of finger dents). The company surveyor (who we asked to be sent round) said that this was expected and how the isotherm works (I would not recommend!) Luckily they sent a plasterer round to fix it, and he said the whole thing (isotherm and all) needed to be redone, and he redid it all. It now looks really good and doesn’t dent with your finger. TBH I wouldn’t recommend this company, I found them impossible to get in touch with and just gatekept at a switchboard and left us in a really vulnerable position and took 6 weeks to fix it.Posted on Monika NiebojTrustindex verifies that the original source of the review is Google. Larry has arrived today with lots of helpful information, been very polite and understanding. Definitely recommended :)Posted on Amanda WilliamsTrustindex verifies that the original source of the review is Google. Ellick came to visit us today, was absolutely lovely, very friendly and explained everything in detail, would definitely recommend!Posted on paul coplandTrustindex verifies that the original source of the review is Google. Had John and Ron at my house this morning fitting a new damp course. They were both friendly and professional. They turned up at my property on time, did a very neat job, explained everything that they were going to do and cleaned up after they had finished.Posted on James WaltonTrustindex verifies that the original source of the review is Google. Larry was very professional! He is very knowledgeable and helped me diagnose my damp issue.
What is a Basement Conversion?
A basement conversion involves transforming an existing basement or cellar into a practical living space within your home. This can include creating an extra bedroom, home office, gym or family room while making the area warm, dry and comfortable through proper damp proofing, insulation and ventilation.
At Home Energy Save GB, we assess structure, moisture and energy efficiency, delivering compliant conversions that add value, improve comfort and protect your property for the long term safely.
What is the Basement Conversion Process?
1. Initial Survey
We carry out a detailed survey of your basement to assess structure, damp risks, ventilation and insulation needs. Our specialists identify any moisture issues, check head height and access, and confirm compliance requirements so the conversion is safe, efficient and suitable for long term use.
2. Design Planning
We design the conversion layout and specify damp proofing systems, insulation and ventilation. This stage ensures the basement remains dry and energy efficient while meeting building regulations, fire safety guidance and your intended use, whether living space, workspace or storage area for years to come.
3. Conversion Works
Our experienced team completes all preparation and installation work, including damp proofing, insulation, drainage solutions and internal finishes. We work efficiently to minimise disruption, maintain cleanliness and ensure every element is installed correctly to deliver a comfortable, usable basement that meets expectations and daily needs.
4. Final Sign Off
Once complete, we carry out final checks to confirm performance, safety and compliance. Home Energy Save GB provides guidance on maintenance and ongoing energy efficiency, ensuring your basement conversion remains protected, efficient and valuable long after the work is finished for your home and family.
Add Value to Your Home With a Basement Conversion
A well planned basement conversion is one of the most effective ways to increase property value. Industry figures suggest a high quality conversion can add between 10 and 20 percent to your home’s overall worth. At Home Energy Save GB, we focus on creating dry, insulated and energy efficient spaces that appeal to buyers while delivering practical living areas for everyday family use.
Basement Conversion Services
Waterproof Membranes
These systems form a protective barrier that prevents moisture from passing through basement walls and floors. By managing water rather than allowing it to soak into the structure, they help maintain a dry and stable environment.
When correctly installed, they support long term protection, reduce the risk of mould and condensation, and work alongside drainage solutions to relieve pressure caused by surrounding ground moisture over time.
Effective Drainage Systems
Designed to control groundwater movement, these systems collect moisture and direct it safely away from the basement. Channelled drainage prevents water from building up behind walls or beneath floors, reducing the risk of leaks and structural stress.
A properly designed setup ensures the basement remains dry and usable, even during heavy rainfall or prolonged periods of high ground saturation.
Sump Pumps
Used to actively remove water from a property, these units collect groundwater in a sump chamber and pump it to a safe discharge point.
Automatic operation provides ongoing protection during wet conditions. Combined with membranes and drainage, this solution helps prevent flooding, controls moisture effectively and keeps basement spaces dry, comfortable and suitable for everyday use.
Benefits of Having a Basement Conversion
Extra Space
Creates additional living areas without extending, ideal for bedrooms, offices or gyms while making better use of existing footprint space.
Property Value
Adds significant resale appeal, with well executed conversions often increasing market value and attracting buyers seeking flexible accommodation long term.
Energy Efficiency
Improves thermal performance through insulation and ventilation upgrades, helping reduce heat loss, control moisture and lower household bills year round.
Better Comfort
Provides a warmer, drier environment by addressing damp issues, airflow and temperature stability throughout the year for everyday family living.
No Extension
Avoids planning complexity and garden loss, delivering extra space within existing walls while maintaining external appearance of your home unchanged.
Versatile Use
Allows flexible room layouts for changing needs, from home working to guest rooms or entertainment spaces as life evolves over.
How Much Does a Basement Conversion Cost?
The cost of a basement conversion varies depending on the condition of your space and the amount of work needed. Converting an existing basement typically falls within a range of around £1,200 to £2,500 per square metre for standard waterproofing and finishes, rising higher if underpinning or excavation is required.
More complex projects can cost significantly more per square metre due to structural work and finishes. Contact Home Energy Save GB for a specific survey and tailored quote based on your home and plans.
Frequently Asked Questions
Do basement conversions need planning permission?
Many basement conversions do not require planning permission if the work remains within the existing structure. However, listed buildings, conservation areas or major structural changes may require approval. Building regulations approval is always required. Home Energy Save GB guides homeowners through compliance requirements as part of our service, ensuring your conversion meets legal and safety standards without unnecessary delays or complications.
How long does a basement conversion take?
Timescales vary depending on the condition of the basement and the complexity of the work. A straightforward conversion may take several weeks, while projects involving damp proofing systems, structural alterations or drainage solutions can take longer. During your free survey, Home Energy Save GB provides a realistic timeframe so you know exactly what to expect before work begins.
How do you stop damp in a basement conversion?
Damp control is one of the most important aspects of any basement conversion. Solutions may include waterproof membranes, cavity drainage systems, improved ventilation and insulation. The correct approach depends on how moisture enters the space. Home Energy Save GB specialises in damp proofing and includes this as a core part of every basement conversion following a free professional survey.
Are basement conversions energy efficient?
When completed properly, basement conversions can be highly energy efficient. Insulation, controlled ventilation and moisture management help maintain stable temperatures and reduce heat loss. Home Energy Save GB designs basement conversions with energy efficiency in mind, helping homeowners create comfortable spaces that do not increase heating costs unnecessarily and support better overall home performance.
What types of rooms work best in a basement?
Basements are ideal for home offices, gyms, cinemas, utility rooms, playrooms or guest bedrooms. The lack of external windows can suit certain uses particularly well. Home Energy Save GB helps homeowners choose layouts that suit light levels, ventilation and heating requirements while ensuring the space remains practical and comfortable year round.
Do basement conversions need ventilation?
Yes, proper ventilation is essential to prevent condensation, mould and stale air. Systems may include passive vents, mechanical ventilation or positive input ventilation depending on the layout. Home Energy Save GB designs ventilation solutions specifically for basement environments to ensure good air quality and long term protection against moisture related issues.
Why choose Home Energy Save GB for a basement conversion?
Home Energy Save GB combines expertise in damp proofing, insulation and energy efficiency to deliver high quality basement conversions. We start with a free survey, provide clear advice and focus on long term performance, not short term fixes. Our approach ensures basements are dry, comfortable and built to last.