1/2 a job, am I taking too much of a risk?

[diy_fun_uk]

keeping this as short as possible. ground floor flat, stone built, 75+ years old. damp on lounge wall at chest height. damp specialist has narrowed down water ingress to faulty downpipe and pointing. recommends as follows:

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EXTERNAL OBSERVATIONS
REAR ELEVATION
Faulty and unsatisfactory downpipe, cracked and boss stone work and pointing also very porous, this being long standing.

RECOMMENDATIONS
Remove downpipe, repoint behind downpipe with a damp proof membrane substrate and replace faulty downpipe. Rake out faulty joints within stonework and cracked stonework, repoint using sand and lime and a recommended water proofer mixed through. Apply 2 coats of enviroseal to porous sandstone to act as a major water proofer as this being one of the main problems of the water penetrating through sandstone.

INTERNAL OBSERVATIONS
PENETRATING DAMPNESS
Lounge back wall adjacent to kitchen and doorway lintel wall

At the time of our inspection there were very excessive visible signs of penetrating dampness supported by moisture readings recorded with an electronic moisture meter revealed evidence of penetrating dampness was located in areas mentioned. Faulty downpipe and stonework i.e. pointing and porous attributing to the main cause of dampness.

RECOMMENDATIONS
Strip contaminated plaster from ceiling to floor levels, Apply a damp proof membrane (D.P.M) to walls, re-plaster, skim coat and finish.

Estimated costs of works - £2,495.00
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my train of thought (partly to reduce costs, partly cause I'm always concerned I'm being quoted for works that aren't required) is to ask for all external works only to be completed and then see if internal damp dries out given the cause will have been rectified. I should point out however the damp has been present for a number of months so will no doubt be x times worse inside wall. company advised no guarantees can be given unless all works completed and that there could be wet/dry/fungal rot that will still need treated but won't be visible unless they remove internal plaster etc.

I've been reading up on unnecessary damp treatments being offered and would like peoples thoughts on whether I should simply fix the cause (exterior) or go belt & braces and get interior repaired as well?

 

[Newboy]

If the person who wrote the report is connected to the company that may do the repairs then I'd question it's validity.

The only way to get an un-biased report is from an independent surveyor

 

[diy_fun_uk]

If the person who wrote the report is connected to the company that may do the repairs then I'd question it's validity.

The only way to get an un-biased report is from an independent surveyor

this is part of my concern re: what I was reading up on, companies affiliated to a certain product try to 'push' its damp solutions even when they're maybe not required. this company 'is' an authorised agent/user for a particular product that carries a 20 year guarantee if all recommended work is completed.

I have another company (builder, not damp specialist, but has completed small maintenance jobs up to full house builds) coming out to assess the damp so will be interesting to see what they say. as I say part of me is thinking get outside repaired and see if inside dries out? visible damp patch is maybe just over a 12"/30cm wide and 24"/60cm high but I do appreciate will be worse inside wall.

 

[Munroast]

Has there always been a damp problem with that wall, or is the problem only recent and fits in with the faulty downpipe?
If the latter, fix the problem and see how it all dries out. Some walls without a DPC are fine and don't cause problems.

 

[jellycat]

I agree with the post above. I am far from an expert on this, but if you have identified the source of the water which is causing the damp, then that should fix the problem? So, fix the faulty downpipe as Munroist says and see what happens.

Also, watch this video, it is very helpful


http://www.spab.org.uk/blogs-videos-podcasts/

 

[foxhole]

If it were mine I would replace the downpipe and repoint.
That's all that should be needed and about 6months for everything to dry out, then replace any blown plaster internally, if sound no need to touch. Electronic damp meters are for use in timber and only detect surface moisture, a drill sample has to be taken to accurately determine internal damp.
The guarantee warning is the usual scare tactic of dodgy damp proof firm and rarely worth the paper it's written on.
General builder could sort this for a few hundred £.

 

[diy_fun_uk]

thanks all. will be interesting to see what builder says, i'll let you know. obviously i'm hoping he'll perhaps recommend exterior work only (or at least as a first attempt at fix) at a cost less then £2.5k!