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JPM Independent Surveyors

4.9

74 Reviews

Opening Hours
Today - 08:00–18:00
  • Monday 08:00–18:00
  • Tuesday 08:00–18:00
  • Wednesday 08:00–18:00
  • Thursday 08:00–18:00
  • Friday 08:00–18:00
  • Saturday 08:00–18:00
  • Sunday 08:00–18:00

About

INDEPENDENT DAMP AND TIMBER SURVEYOR.
I provide specialist damp investigation reports and timber reports with solutions to fix the problems. I also offer Spayed foam evaluation reports.

Dampness is often misdiagnosed by contractors.
Quite often the correct solution is simple and inexpensive.

I AIM TO RESPOND TO EMAILS WITHIN A FEW HOURS -

I am not a contractor, I am a surveyor. I do not carry out remedial damp proofing or building works so you can rest assured that my reports are completley impartial.

Experienced qualified independent damp and timber surveyor.
: Dampness
: Condensation
: Mould
: Timber decay
: Woodworm
: Ventilation
: Spayed foam evaluation.

CSRT Qualified.
Property Care Association.

20+ years experience, fully insured, I provide for home owners, tenants, estate agents, landlords, architects and property pre-purchase.

Covering areas of North London, East London and West Essex.

What we do

  • Damp proofing and timber preservation services

    • Condensation and humidification control
    • Timber treatment services
    • Woodworm treatment
    • Injection damp courses
  • Mould

    • Mould investigation
    • Mould survey
  • Surveyors

    • Building Surveyors
    • Damp proofing surveyors
  • Builders

  • Specialised building trade contractors

  • More Services

    • independent
    • timber
    • rot
    • water damage

Customer reviews

Why you can trust these reviews

All reviews are verified as being genuine and a true customer of this trader.

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100% of the reviews we publish have been through our stringent moderation process.

4.9
74 reviews
Customer Service
5.0
Quality
5.0
Value
4.9
Sort by
Detailed, professional damp survey and clear recommendations
Customer Service
Quality
Value
Jason carried out a damp and timber survey at my terraced property in Walthamstow and I was very impressed. He was polite, respectful and punctual, and he took the time to explain what he was looking at and why. The report itself was extremely detailed and clearly written, with photos, measurements and a sensible explanation of likely causes. It set out the priority actions in a practical way, including the key items around lowering external ground levels and a French style drain at the front bay, improving sub floor ventilation, and dealing with localised rising damp on the entryway party wall, plus guidance on inspecting and treating sub floor timbers. What I valued most was that it read as genuinely independent and focused on getting to the root cause, rather than pushing a one size fits all solution. He also included estimated cost ranges to help me plan and then obtain like-for-like contractor quotes. I would happily recommend Jason to anyone who wants a thorough, professional damp investigation and clear next steps.
Customer in Greater London Posted on 25/02/2026 , work completed 11/02/2026
Thorough, detailed and very helpful.
Customer Service
Quality
Value
We started getting damp patches in our hallway which we suspected to be rising damp. We had a full survey done by Jason, on the recommendation of some friends, and can thoroughly recommend his service. The report that Jason produced was thorough but also accessible and he gave clear, impartial recommendations for how to address the various issues that he found. As first-time home owners with no experience in getting building works done, we particularly appreciated Jason's straightforward recommendations and explicit instructions on how to use his report when reaching out to builders!
Customer in Greater London Posted on 17/01/2026 , work completed 30/11/2025
Damp survey
I was pleased with the damp survey done by Jason as it helped me identify the precise causes of the ingress of water that led to damp in my kitchen. I can now use this report to ask the freeholder / managing agent to make sure the exact work needed to remedy the situation gets done and try to use the recommendations to get better ventilation in my flat.
Customer in Greater London Posted on 01/01/2026 (Reviewer did not use service)
Detailed and understandable damp and timber survey
Customer Service
Quality
Value
Jason conducted a damp and timber survey after damp had been flagged by a homebuyer's survey. Jason's report was detailed and expertly written, but understandable and with plenty of explanatory notes and context. It was accompanied by unbiased recommendations and price estimates for steps to take to combat the issues (none of which seem over the top or wildly expensive), and useful suggestions of how to stay on top of things in the longer term. Communication throughout was excellent and despite an unavoidable last-minute change of date the report was still delivered within the original expected timeframe. Would thoroughly recommend Jason.
Customer in Greater London Posted on 29/11/2025 , work completed 07/11/2025
Efficient, professional and clear
Customer Service
Quality
Value
Jason conducted a specialist damp survey for us after our home buyer's survey raised a few possible damp issues. He was quick to respond to our enquiry, was able to conduct the survey the following week and sent the report the next day. His role as an independent surveyor reassured us that we wouldn't be told extensive repairs were needed unnecessarily. His report was clear and came with estimated costs for any repairs needed, as well as recommended products to monitor damp. Overall, a great experience, thank you.
Customer in Greater London Posted on 19/06/2025 , work completed 18/06/2025
Damp in the kitchen
Customer Service
Quality
Value
We employed Jason to carry out a damp survey to our kitchen. He was very thorough and professional and is clearly an expert in his field. He took photos of areas to illustrate the cause of the damp and to clarify what action needed to be taken. He was quickly able to identify the cause of the damp. His report was clear and informative using a system whereby he indicated which work needs to be carried out urgently. He is totally independent so has no investment in finding extra/unwanted work for suppliers to carry out. We felt reassured that all his recommendations were made according to what he found. He took samples of plaster away to ascertain the cause of the damp. In addition, he assessed other areas in the house and made recommendations for action to prevent damp arising in the future. I would highly recommend this company
Customer in Greater London Posted on 19/01/2025 , work completed 13/01/2025
Fast work, and follow up recommendation
Customer Service
Quality
Value
Jason was very professional and gave a detailed report with recommendations for work to be completed. Responded to my follow up email with good advice
Customer in Greater London Posted on 03/01/2025 , work completed 11/10/2023
Damp and timber survey
Customer Service
Quality
Value
Jason was great. He did a thorough job surveying the property, provided recommendations and costings, and advice for better prevention in future. The report was produced quickly and was clearly laid out. Highly recommend Jason!
Customer in Greater London Posted on 26/08/2024 , work completed 21/08/2024
Professional, independent full service - exactly what I was after
Customer Service
Quality
Value
Jason Mahoney was professional, communicative and expert. His full-range investigation covered all damp, ventilation and considerations considerations. His report, provided a few days after the investigative visit was full of actionable recommendations and accompanied by a series of specific product recommendations. I chose JPM Surveyors because I wanted a third-party expert survey that was not linked to a contractor seeking to win business for follow-on works. That's precisely what I got. While not cheap, this felt like an investment worth making. Highly recommended.
Customer in Greater London Posted on 27/07/2024 , work completed 12/06/2024
Great guy, super helpful, recommended
Customer Service
Quality
Value
Jason has helped me out with a damp survey and report twice now and I'd recommend him without hesitation. He's always on time, he's got some great tech and is very thorough with his surveys, explains everything really well, delivers the report quickly (if you need one), and is happy to answer extra questions afterwards. Highly recommended if you need someone knowledgeable, trustworthy and independent.
Customer in Greater London Posted on 03/03/2024 , work completed 28/02/2024