Damp Proofing Question

Which is the best remedy to stop damp once and for all!!!

Hi, I have had various quotes to resolve damp issues on external walls. mostly rising damp, with some penetrating. And I have had numerous remedies suggested, can anyone give me the best answer please.

4 Answers

Best Answer

hi, for rising damp fit a new pvc dpc, this will stop rising damp once and for all. many thanks vince at london-damp-tanking

Answered 2nd Jun 2011

london-damp-tanking

Member since 26 Sep 2010

Hi Hazel, it's very difficult to give advice with regards to damp without doing a site survey. There are lots of elements to consider. Do you have suspended floors or concrete? If suspended, is there sufficient void ventillation? You could have the Walls injected, to stop future damp escalating but aditional work is required to remove hydroscopic salts from the plasterwork. In general plaster should be knocked off the Walls 1metre above floor however this shoukd really be 400mm above the highest water mark. Then re-surfaced with seika or equivellant, could also be due to condensation, no flue ventilation if chimneys have been bricked up. I would advse you google a specialist. Peter cox is national and pretty good.. Hope this helps. Gareth

Answered 2nd Jun 2011

AGL Heating & Building

Member since 1 Oct 2009

The best source of this information with regards to finding the best solutions would be the Property Care Assocaition British Board of Agreement and perhaps a product manufacturer. If a contractor is not trained in using a particular system and advise you through the products used and what they are for, it's not really a great indicator of knowlege. A lot of the time re generated hear say on what works and the need for companies to get rid of the massive stock piles of injection creams, means bad installs and solutions are always going to happen.

The only system that I can have a major insurance company back for 30 years, is a tanking system. I once asked my loss adjuster about injection and he nearly laughed out a lung. It's the three year turn over he said. Start up a firm, inject a few walls, take the plaster off re plaster it, leg it, and in three years it's back and worse than before but the contractor is long gone, see how many damp firms were established longer than 4 years prior, there aren't many!

I know of many great "systems" but cherry picking one aspect of it (generally the cheapest part) and figuring it is the sole cure to the issue is a miss guided happening we see all the time. Most people will always say tanking is a step too far unless it's for a basement or marine application and it's expensive, but to be honest, why risk it. It may only cost a few hundred pounds to have it injected and re plastered, but it's a cycle to be paid out over and over again, just because a pruduct is guaranteed, does not mean the provided paperwork guarantees the installers chosen application of it nor his or her method.

I hear by guarantee this product for 30 years it says, the manufacturer says, well it is, but your contractor installed it wrongly, or it's only part of a system, so it won't work on it's own.......absolute mine field.

If the diagnosis of damp is correct, then a system will exist to cure the issue. Proper diagnosis, and a trained installer with an insurance backed guarantee, and a guaranteed system from a manufuacturer and you won't go wrong.

Answered 2nd Jun 2011

Holcombe Building and Restoration Ltd

Member since 12 May 2011

Hi Hazel

It can be a big headache when you not only have rising damp but also penetrating/lateral damp.
There are many different approaches to remedy these issues from externally re rendering or if render is bridging with the external ground then either cut bottom 150mm away or put a cut at 150mm to help stop bridging and fill cut with a external mastic.Also you can look at waterproofing the brickwork with a sealant that lets the wall breath but does not allow rain to enter.

Internally if you do have rising damp and your external and internal ground levels are of similar height and not earth retaining(External high ground)then you will need a drilled and injected DPC whether its injected under pressure or a cream DPC by means of a large caulking gun,this is less messy and a more commen means to DPC now,it also works and reacts to the damp.
Also with rising/penetrating/Lateral Damp you will most likely have signs of damp on the internal walls and see tide marks at the highest point of damp(these may be wet or have dried out)the plaster will have to be removed as this is now contaminated from ground salts Chloride and Nitrate that have been drawn up and impregnated the brickwork and plaster.

Hmmm Holcombe saying most Remedial Firms trading 3 years and disapearing i dont understand! If as a company you know what your doing and talking about,why would you cease trading?
I previously worked for one of the longest established firms in Property Care/Remedial Treatments and during my 14 years with them ive seen lots of other Remedial Companies go from strength to strength. Maybe he has met a few unsavoury ones!!
I agree the person needs to know what theyre doing/how theyre doing it and information and knowledge of the product they are trying to sell and use.

The Property Care Association have many members that are accredited and Surveyors that are CSRT registered BUT i have worked with many Surveyors and some do things different to others but they are all CSRT registered and compitant in theyre work.

As for products and help! I use 5 companies for varied products:
Rotafix
Twistfix
Delta
Vandex
Wykamol

Wykamol produce chemicals for Remedial works and Damp proofing Additives.

I would advise check up and see if these companies/sole traders are accredited and compitant in theyre work. Maybe find out how long they have been trading,Do they have a portfolio and even down to theyre Public Liability Insurance.

Hope this was of some help.

Scott Cannon.

Answered 2nd Jun 2011

Cannon Preservation Ltd

Member since 21 May 2011

Need help with your project?

We have tradesmen ready to help you. Post a job, read reviews and hire today.

Post a job

Need some help?

Post a job on MyBuilder to find quality, local Damp Proofing Specialists who can help you with your project.

Search all questions