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Endorsed by Which? Trusted Traders

JPM Independent Surveyors

Profile thumb jpm

61 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

What is a Which? Trusted Traders Islington Trading Standards Approved Endorsement?

Which? Trusted Traders has partnered with Islington Trading Standards to create an Islington Trading Standards Approved endorsement. In addition to our standard trading standards assessment, this trader has had a DBS check and is subject to a Trading Standards intelligence check.


I provide specialist damp investigation and timber reports with solutions to fix the problems.

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


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 competently impartial.

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

CSRT Qualified.
Property Care Association.
Expert Witness Institute.
PCA Qualified Technician in Structural Waterproofing.

20+ years experience and 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.

How can we be so sure?

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

61 reviews
Customer Service
Sort by
Prompt and efficient attention
Customer Service
I required a building survey to be carried out on inadequate work done by a roofing contractor. I contacted Jason Mahoney on the recommendation of Which Trusted Traders. He replied promptly, fixed a date and provided me with a full scope of the proposed survey. On the day he arrived promptly, undertook a very thorough survey and a full and very detailed report with a comprehensive list of recommendations was provided the following morning. I can thoroughly recommend his services.
Eric in Greater London Posted on 18/07/2021 , work completed 18/07/2021
Brilliant service, fast report, thorough survey. Would highly recommend.
Customer Service
Jason was highly responsive and professional from our first contact, and liaised with our estate agent to enter the property. Despite being very busy at the moment, Jason performed the survey in a very short time frame for us and returned the report on the day of the survey. The report is thorough, and the advice was clear and reasonable. I would highly recommend Jason and couldn't have expected any better service.
Harvey in Oxfordshire Posted on 16/07/2021 , work completed 10/07/2021
Independent damp survey-- excellent service
Customer Service
Jason Mahoney responded very quickly to my request for an independent survey and delivered his report and recommendations within 24 hours of the survey. He provided a clear and comprehensive report with useful recommendations to address the dampness in my flat. I was impressed with his detailed explanations of the causes of the damp problems and how he considered the options for dealing with the problems carefully. His independence from commercial vested interests was invaluable in helping me to make balanced decisions about the best way forward.
Customer in Greater London Posted on 05/07/2021 , work completed 03/07/2021
Instrusive Damp Survey
Customer Service
Jason carried out an intrusive damp survey. He responded quickly to the request to do it, and carried it out efficiently. He was happy to explain what he was doing along the way. He produced the report in a couple of days, and it was very clear and well explained. He seems to be very well informed about this area, and we are grateful for his help.
Ed in Somerset Posted on 29/06/2021 , work completed 15/06/2021
Exceptional, reliable and thorough
Customer Service
I contacted Jason last minute as we were against the clock to get a damp and timber report for our mortgage offer (the condition appeared in the offer paperwork and we had to complete within days). Jason really went above and beyond. He luckily had a cancellation the next morning. Jason inspected the property, and provided a thorough and flawless report with full costings (and lots of helpful additional information) before the end of the day. He really saved the day and we can’t thank him enough. In addition to allowing us to meet the deadline- the report he provided gives us the confidence that we understand the damp issues (very old property), and the work involved before we purchase. Truly exceptional- thank you!!
Customer in Greater London Posted on 22/06/2021 , work completed 21/06/2021
Great work
Customer Service
Jason surveyed a property we wanted to buy after damp issues were raised. His report was returned to us the same day as his inspection, but was completely comprehensive and also really easy for someone who has no experience of reading technical reports to understand. His professionalism was such that even though his report led to us negotiating a big price reduction on the property, the vendors told us that Jason was a great guy and that they were really impressed by his work. Can't recommend him enough.
Customer in Greater London Posted on 12/06/2021 , work completed 15/05/2021
Damp Report Pre purchase
Customer Service
Jason gave a highly detailed and informative report. The report was detailed with photographs showing areas of concern, remedial action recommended and overall opinion on condition of property. Extra information was also attached to the report with some product recommendations and advice as to why damp occurs and how to manage if not eradicate it.
Customer in Greater London Posted on 31/05/2021 , work completed 31/05/2021
Clear and Informative Surveyor
Customer Service
We hired Jason to do an independent damp report for our basement flat. After having a few "free" surveys with the big damp companies in the past we were left confused about what was the cause and fix of the problem. Jason suggested modern solutions for damp proofing that are were not suggested to us by the previous companies. He provided a detailed report with suggestions for materials which has enabled us to quickly get quotes from lots of different companies. Overall he has saved us lots of time and money!
Customer in Greater London Posted on 10/05/2021 , work completed 04/05/2021
Excellent service
Customer Service
Arrived exactly on time, clearly explained issues he identified, written report very thorough and couldn't have been clearer.
Customer in Greater London Posted on 09/05/2021 , work completed 07/05/2021
Professional and detailed recommendations
Customer Service
I wanted a second opinion after a free damp survey suggested rising damp of my exterior walls. Jason was able to pinpoint the issues in my apartment and identified key remediation areas that fit the evidence. I would recommend his services for an impartial report of your damp issues.
Henry in Greater London Posted on 08/05/2021 , work completed 06/05/2021