Early C19 Damp Grade II listed bungalow

[tvrulesme]

I am in the process of buying a Grade II listed bungalow which has been vacant for the last 4 years. The Building Survey RICS Level 2 (Structural Survey) has unsurprisingly high-lit some damp issues.

• To the sitting room wall with rising and penetrating damp to either side of the French doors opening out to the garden.

• There is further dampness evident to the sitting room to either side of the chimney breast and the chimney breast itself.

• Dampness was evident to the chimney stack in the dining room and also to the walls to the bay window sections.

• There is excessive dampness to all walls including penetrating damp to the bedroom.

• Penetrating damp and rising damp was evident to the walls adjacent the opening to the bathroom and also the wall adjoining the bedroom/study area.

• Further dampness to the bedroom/study extension to either side of the French doors at high and low level with excessive penetrating damp and rising damp to the corner of the wall adjacent the kitchen.

The loft area seems to be fine.

Our mortgage company has requested a Timber and Damp survey from a PCA association member which is scheduled to be conducted today. My plan is to carry out any remedial and monitoring work suggested in the report but as this will be a holiday home for my family which will be vacant most week days and used by us over weekends I was wondering how best to tackle ventilation and/or dehumidification as well as drying out the existing damage.

My initial thought is to install a desiccant dehumidifier like the Ecor pro DH1200 DryFan 12L Desiccant Dehumidifier in the roof area. Given this is a listed building I will need to retain the original fabric of the building wherever possible but I do have a number of existing vents or openings to the outside which could be repurposed.

Can anyone tell me if this is an awful idea, if a ventilation system would be better or if I should be thinking of something else entirely?

I have attached a floor plan with as many details as I think would be relevant to help.

Totally understand that the topic of rising damp is highly controversial so if you could please play nicely in your replies that would be fab ;)

floor-layout-damp.pdf

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[dewaltdisney]

You must be a masochist as this is will be a money pit. There will be a never-ending stream of trades and authorities with their hands out for money. The fact is that as a holiday home that will be left unoccupied for a large part of the year it means that atmospheric damp adds to the equation of the rising damp construction defects. Holiday homes never stack up, the money you save on accommodation never equates to the outgoings and when you sell you get done for capital gains, or your family is lumbered with it after death duties.

This sounds like I am p*ssing in your bonfire and I do not want to do that but you need to think clearly about this.

DWD

[arco_iris]

Very comprehensive post, tvrulesme. What's your construction, random stone, dressed stone, or brick?

DWD has a legitimate opinion, and my reply which overlaps is in similar vein.

Just my thoughts, not offering any specific advice as I am no expert. But I do live in a C18 single-storey GII Listed Building so have read & learnt a lot.

"C19 bungalow" seems a contradiction of terms, bungalows by definition didn't really exist then so I'm thinking you mean a cottage, but of course that's a moot point.

Buildings of that age were of solid wall construction (definitely no cavity as such*) and, although cement was invented in 1824, more often than not constructed using lime mortar until the very late 19C. Because they didn't know any different, equally they had no damp proof course, underfloor membrane, or even guttering. None of it mattered then in your average buildings.

Now to my mind, 21C builders work to 21C methods with 21C materials they get from 21C builders merchants, and similarly, present day surveyors the same, neither basically understand older buildings.

Consequently you get (i) previous maintenance carried out wrongly and (ii) 21C surveyors giving incorrect diagnoses (iii) staff in Mortgage Provider Call Centres who do not have a clue but follow a script.

So first of all, is your mortgage offer dependent on a qualifying outcome?

You say "unsurprisingly", so you know what you've let yourself in for?

Is there any evidence (paperwork - holes drilled in walls) of chemical dpc? (bad).
Any evidence of repointing (outside), replastering (inside)?
Any evidence of the outside being painted with modern masonry paint instead of limewash?
Has internal decoration been carried out with modern vinyl emulsion instead of distemper?

To be the custodian of a Listed Building, with any conscience, you've got a lot to consider.

* "Solid" walls usually have an outer face (now called a leaf) and an inner face (ditto) and as they went along they chucked all the rubbish in between. So they're not totally "solid", but they're not "cavity" either - usually full of mud.

[Someone-Else]

sitting room wall with rising and penetrating damp

dampness evident to the sitting room to either side of the chimney

Dampness was evident to the chimney stack

dampness to all walls

Penetrating damp and rising damp was evident to the walls adjacent the opening to the bathroom

Further dampness to the bedroom/study extension

My 2p worth, there does seem to be a lot of damp, and as its not going to be occupied all year, what is going to keep it warm in winter? I understand a challenge, but sometimes you have to walk away, then you also have to wonder why

has been vacant for the last 4 years

[tvrulesme]

Love the replies so far. This has raised several parts so I'm going to try and address them separately. Firstly have I gone mad and what's my motivation?

You must be a masochist as this is will be a money pit. There will be a never-ending stream of trades and authorities with their hands out for money.

So masochist is a bit strong but almost 100% sure this is a mid life crisis. Doing the maths this works our far cheaper than having an affair and getting a divorce

To give a bit of context, my father was an architect but spent his whole life renovating and updating the houses we lived in which meant I spent 98% of my youth living on a building site. I have a very deep passion for buildings and architecture. This is my passion and my hobby. I've spent the last 10 years doing up our period Edwardian House and frankly after loft conversions, extensions, rejigging and renovating we've frankly run out of things to do. This coupled with the fact that the family are unwilling to live as their main property being a building site leads us to look at a project house which we don't actually live in.

So I'm bored. I totally totally get that a "project" with a property of this age, character and consequent restrictions is another world altogether but this is kind of the point. It will keep me going and interested with stuff for years, possibly decades to come.

I'm very very fortunate that money and profit is not my motivation here. I've done well out of life and have the funds but absolutely not prepared to be taken for a ride by builders, councils and surveyors which is why I come to forums like this to keep me in check and informed. I do not in any way expect to turn a profit on this but I do expect to turn it in to a place I love being in and feel a pride in my work.

I've clocked up many hundreds of hours of research on historical buildings, conservation, legal implications and the planning process so I believe that I am well informed to make this frankly crazy decision. I 100% know this will be tough, and painful, and expensive but I also expect it to be very fulfilling. I want this building to stop being under threat from the likes of damp and a lack of love and to revert a bunch of the 21C changes which were never intended to be done to it in the first place.

[tvrulesme]

My 2p worth, there does seem to be a lot of damp, and as its not going to be occupied all year, what is going to keep it warm in winter? I understand a challenge, but sometimes you have to walk away, then you also have to wonder why "has been vacant for the last 4 years"

So firstly why vacant for the last 4 years? Sadly the previous owners died 4 years ago, they did not leave a will. It led to a very complex probate where the family no longer talk to each other other than via solicitors. This is well documented in the legal docs etc.

[tvrulesme]

My 2p worth, there does seem to be a lot of damp, and as its not going to be occupied all year, what is going to keep it warm in winter?

Yes there is a lot of damp. I'm still waiting to get the final damp and timber survey back but my strong suspicion is that this is mainly due to some suspiciously high ground levels around the affected areas caused by a recent introduction of a patio. The patio footprint does appear to marry up exactly with the damp walls internally

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As well as a lack of ventilation over a period of 4 years. There also appears to be some leakage from the kitchen sink which has penetrated through one wall so this needs fixing too.

In terms of what is going to keep it warm in the winter, I am a bit of a techy guru. This is a big part of my day job. I intend to put humidity and temperature sensors absolutely everywhere, monitor the hell out of it. Calculate the dew point and fire up the heating accordingly. The final piece of the puzzle is really my original question of whether to install a Desiccant Dehumidifier in the roof area to both circulate air while we're not there as well as expelling moisture until it eventually falls within acceptable levels. Again monitoring will be key to this. I frigging love my data

[tvrulesme]

Very comprehensive post, tvrulesme. What's your construction, random stone, dressed stone, or brick?

Thanks so much for the response. So from the building survey

• The external walls are approximately 300mm in thickness and are of solid brick construction with a paint finish.

• To the side extension the walls are approximately 275mm in thickness and are of cavity construction. The walls have a part rendered finish.

• Cavity walls are formed by two skins of brick, block or masonry with a gap between them. The two skins are held together by wall ties.

"C19 bungalow" seems a contradiction of terms

100% right. I thought I was making life easier by using this to say it's a single storey building but you are correct this is indeed a cottage.

Now to my mind, 21C builders work to 21C methods with 21C materials they get from 21C builders merchants, and similarly, present day surveyors the same, neither basically understand older buildings.

Yes this is brilliantly put. There is a lot of evidence of this in the property (including a half full bag of gypsum plaster in the garage ) so I will need to over the years slowly go back to basics and reintroduce breathable materials. Not going to be able to do this all in one go because of time and money but we will get there eventually.

So first of all, is your mortgage offer dependent on a qualifying outcome?

Yes an no. still working on this one but I am very very persistant

Is there any evidence (paperwork - holes drilled in walls) of chemical dpc? (bad).

Fortunately not that I can see

Any evidence of repointing (outside), replastering (inside)?

Replastering yes unfortunately and will need replacing with lime plaster at some point

Any evidence of the outside being painted with modern masonry paint instead of limewash?

Yes, damn these people. Luckily for me it's flaking which may or may not mean easier (non-abrasive) removal.

Has internal decoration been carried out with modern vinyl emulsion instead of distemper?

I strongly suspect the answer to this is yes

[dewaltdisney]

Now I understand your motivation and means it makes more sense. You are going into this with your eyes open and you have the knowledge and resource to get to where you want to be so good luck with it. I can understand the remote project part and the ability to go home from a building site to a comfortable home, I did this to a certain extent when I refurbished one of my son's houses a few years back.

This will be an interesting project so please keep posting progress and photos to keep us up to date

DWD

[arco_iris]

Have you yet been into the loft, any sign of bats?

[tvrulesme]

Have you yet been into the loft, any sign of bats?

Ha. yes I have. No sign of bats fortunately. The roof is not the original one and the timbers are not that old. Could use a little organisation to be fair. Forgive the awful camerawork but here's how it looks

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[tvrulesme]

So damp and timer survey report has arrived. Basically 3 major remedial works recommended.

• Remove external impervious coating and re-point brickwork

• Form a trench at the wall/path junction to a depth of 150mm below the physical damp proof course or internal floor level

• Remove any damp plaster to approximately 300mm past the last detectible evidence of dampness and re-plaster using a suitable breathable plaster

All sounds pretty pragmatic and I found the surveyor to be very good at communications and he had a very good understanding on period buildings. Very pleased not to see a recommendation for chemical DPC on that list!!

So this raises a further question. In terms of the French drain there is one long section which would be 20.4m long which at a 1% gradient would require a drop of 204mm until it gets to the rainwater drain.

There is another option which is to split the french drain into two sections with one going to the front of the property and one to the rear. Question is, would I be allowed to connect to this rainwater drain on the street from the French drain given that the downpipe (yellow arrow) already discharges into it? If I would be allowed would I be allowed to create the connection underground?

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