Help needed redry rot.

We've got dry rot under our stairs.

A company has been round and told us that all the floorboards in hall will need replacing with treated floorboards. Plaster will need replacing to height of 1 metre (up to Dado rail) by 3 metres wide. Two air bricks will need installing.

The quote has come in at £3000 for a weeks work.

This seems fairly expensive considering the quote effectively covers

1) what the cost of floorboards are (hallway measures 2 metres by 6) 2) 2 people for 2 days to lay floorboards 3) install 2 airbricks (cover one exisitng air brick which is level with pavement outside (this is where water has been coming into the house) 4) the cost of a plasterer for a day and his material. 5) treating all new wood with dry rot prevention chemicals 6) finsihing work

Can anyone recommend any companies in North Manchester/Bury area which deal in this type of work?

Regards

Reply to
Steve Fisher
Loading thread data ...

We've got dry rot under our stairs.

A company has been round and told us that all the floorboards in hall will need replacing with treated floorboards. Plaster will need replacing to height of 1 metre (up to Dado rail) by 3 metres wide. Two air bricks will need installing.

The quote has come in at £3000 for a weeks work.

This seems fairly expensive considering the quote effectively covers

1) what the cost of floorboards are (hallway measures 2 metres by 6) 2) 2 people for 2 days to lay floorboards 3) install 2 airbricks (cover one exisitng air brick which is level with pavement outside (this is where water has been coming into the house) 4) the cost of a plasterer for a day and his material. 5) treating all new wood with dry rot prevention chemicals 6) finsihing work

Can anyone recommend any companies in North Manchester/Bury area which deal in this type of work?

Regards

Reply to
Steve Fisher

I'm no expert or even sure of this but if they are replacing the woodwork that has rotted and fixing the problem causing it why treat the new wood ? Or will any remaing traces of rot spread to the new wood.

I'll do it all baring the plastering for a fiver. ;-)

Mark S.

Reply to
Mark

Strictly speaking it shouldn't be necessary because the conditions for dry rot to establish and grow will have been removed - i.e. a moisture source of the correct amount of moisture and lack of ventilation.

However, the common practice is to sterilise all surfaces and materials with a suitable solution.

A litre of Cuprinol Dry Rot Killer is about £7, so in the context of the cost of the job and what an outbreak can cost, it's pretty much a no-brainer to use it on the new wood.

BTW. You're selling yourself too cheaply.... :-)

.andy

To email, substitute .nospam with .gl

Reply to
Andy Hall

Chances are all you really need to do is find the source of the moisture that causes the dry rot (a badly named thing if ever there was one), add some ventilation, slap some dry rot killer around and let it all dry out. There may be a leak from cracked render or a gutter or damp proof course letting moisture in. If you have a washing machine under there that can cause all sorts of damp and condensation problems. I have the same under my stairs from the washing machine and its drain outlet. Replacing floorboards many metres away seems total overkill IMO but then I haven't seen your house.

Dave Baker - Puma Race Engines

formatting link
You find somebody to love in this world you'd better hang on tooth and nail - the wolf is always at the door. (Don Henley - In A New York Minute)

Reply to
Dave Baker

I had a dry rot afflicted floor replaced 30 years ago and they neither removed the cause of the problem nor sterilised the brickwork and surrounding timber. 10 years later it was back and I did it myself this time, cut well back, burned and soaked the brickwork, everything according to the text book and it's not returned.

Today I witnessed some carpenters, on bonus, replacing a nearby house floor ruined with dry and wet rot. In their haste they removed the timber without ceremony, treading on spores, no effort to sweep up infected debris. New joists were rapidly installed on a 'that'll do' basis and floorboards thrown down without any clamping up. Their attitude was that the new wood was pressure treated and it would 'last long enough'....... . Not my idea of a proper job, so be warned and watch the builders if you do place the contract. IMHO it's better to go OTT when it comes to Dry Rot, rather than regret it years later.

But £3 k does sound very expensive.............(and a fiver way too cheap). I reckon about £1k would be fair if properly done, using round estimates for your list of jobs and materials above.

BAH

Reply to
BAH

Does the £5 cover travelling expenses or are they additional.

Reply to
Steve Fisher

The path outside is concrete. The dpc is higher than airbrick. Your right in saying that when it rains heavily i believe a natural run off point will be into airbrick.

Reply to
Stephen Fisher

There are several forms of wet rot but I believe only one kind of dry rot.

Wet rot happens generally when there is a high level of moisture and there are various types, the most common being cellar fungus, which is almost certainly what afflicted your bathroom. Basically the fungus is limited to the wood and to wet areas at that and causes to disintegrate along the run of the grain. Window cills and fencing are other prime candidates. The fix is basically to remove the source of water, to mechanically replace or repair the wood and to treat.

There is another wet rot fungus called mine fungus which happens under similar conditions but the wood tends to crack into cuboid shapes across the grain. For this reason it is sometimes mistaken for dry rot which can also leave the timber with this appearance.

Dry rot thrives in somewhat drier conditions of the wood, the key factor normally being lack of ventilation plus a source of moisture. The fungus has the ability to obtain water from a remote source as well through its strands which can penetrate masonry. There are various appearances at different stages ranging from a white cotton-wool appearance of the mycelium (growing part) to the purple/brown of the fruiting body. Very often, there is a distinctive mushroomy smell which is difficult to describe, but once you've smelt is unmistakeable.

I once saw an extensive outbreak in an old church hall. It was really quite revolting with strands extending over an entire wall behind some panelling.

The treatments tend to be quite draconian because of the ability of the fungus to penetrate masonry. There is a debate as to whether ripping off plaster and sterilising brickwork is really necessary, or contractors trying to put more meat in the sandwich. The counter theory runs that if the moisture supply is removed, the ventilation fixed and the timber replaced with pressure treated, then there should be no need to sterlise the masonry.

Rentokil's web site has some pictures of the various fungi.

formatting link

.andy

To email, substitute .nospam with .gl

Reply to
Andy Hall

It might help to think of it more like a pot plant. The soil is the wood, and it breaks down the wood to grow branches across rock and brickwork, and through mortar and behind plaster, to search out more wood for food. The branches can carry the water it needs, so it is capable of infecting some wood which isn't damp once it gets started. The flowers (fruiting bodies) are like white cotten wool balls, and the seeds (spores) are a dark red or brown powder which the flower throws out some feet from it. The powder can lay around for years after the fruiting bodies have gone, if not disturbed.

It requires a particular humidity range which doesn't occur naturally in the UK, but can be found in poorly ventilated enclosed spaces in houses. It will actually die all by itself if exposed to good ventiallation -- you never see it growing outdoors in the UK. It's natural habitat are caves in the Himalayas where it feeds on the dead tree roots which penetrate the cave walls. It was brought back to the UK in wooden ships, where it also became a major problem.

I found a small outbreak under a bath. It was in a tiny block of wood fixed to the wall. The branches had grown out along the wall to find some more wood. However, it's blind, and it had managed to stear a course which missed all the other wood, and then it ran out of energy from the original tiny piece of wood and died (fortunately). There was no sign it had ever managed to grow a fruiting body.

Reply to
Andrew Gabriel

Thanks for the description guys, makes a bit more sense now the extent of the treatment. Still think I'd do it myself and save a couple of grand. :-)

Mark S.

Reply to
Mark

From what I've read, the rot will not spread through dry media, but it can spread through damp media that would otherwise offer no nutritional value, e.g. plaster and brickwork. This is what especially distinguishes it from other rots.

1) sort out the ventilation. this alone can kill dry rot off almost completely.

2) remove the source of the damp - without damp the fungus cannot live, period. Spores can lurk in plaster and wood, but unless you remove and replace all timber and plaster then you'll not get rid of them.

3) replace any structurally damaged timber. This isn't the same as "infected" timber, but for example joists where the rot has attacked them to the point where they have become seriously weakened.

4) whilst you've got the floor up, treat the timbers. If you replace joists then you may as well replace them with pressure treated timber. Don't cut the end that is adjacent to the air brick.

Of course, this all depends upon the extent of the problem. From your description it doesn't sound like it warrants the draconian measures that had been proposed.

cheers Richard

-- Richard Sampson

email me at richard at olifant d-ot co do-t uk

Reply to
RichardS

Petrol, makes a cheap (somewhat dangerous!), dry rot fluid. Need to ensure the local area ventilation is sorted before any use :)

Reply to
John Jardine

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.