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Where is our damp proof course?
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Jessiemessy
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Where is our damp proof course?
We are thinking of digging up the garden and attaching decking to the back of the door. We wanted it level with the back door so you aren’t stepping down. However, looking at the back of the house, there’s a concrete line that goes around. Is this the damp proof course? As I can’t see where else it would be, unless we don’t have one. And want to make sure the decking is above any damp proof course. Bear in mind we have a crawl space and the concrete line would be where the crawl space begins (the roof of it). Our house is from the 1960s in case that helps
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ayjay
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Where is our damp proof course?
The dpc is in the wide mortar joint immediately above the air-brick.
The decking will ideally be 150mm below the dpc, not above it.
The decking will ideally be 150mm below the dpc, not above it.
One day it will all be firewood.
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Jessiemessy
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sammy.se
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Where is our damp proof course?
Ayjay's advice should be taken strongly. That 150mm gap means that rain won't bounce off the deck, over your Damp Proof Course.
If you build a decking closer than 150mm below the DPC, you are inviting a bunch of damp issues. If you have a cavity wall, then less of a risk, but still not ideal.
I have personally done experiments in my garden and I can tell you rain bounces!! and gets absorbed into the brick wall.
If you build a decking closer than 150mm below the DPC, you are inviting a bunch of damp issues. If you have a cavity wall, then less of a risk, but still not ideal.
I have personally done experiments in my garden and I can tell you rain bounces!! and gets absorbed into the brick wall.
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wes56
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Where is our damp proof course?
The brickwork indicates a cavity wall.
The air brick indicates a suspended floor.
The thick bed of mortar appears to be a DPC of sorts.
However, both airbrick & DPC are too high for the joist tails in a suspended floor.
In best practice the Joists should sit on the DPC, & so should the air brick - but having a cavity then maybe the joist tails are protected by a lower DPC on the inner skin.
Whatever, as above,
any deck as proposed will only bring you possible difficulties.
FWIW, decks are 20yrs out of date, & are often looked on with disfavour by mortgage surveyors & some house buyers.
The air brick indicates a suspended floor.
The thick bed of mortar appears to be a DPC of sorts.
However, both airbrick & DPC are too high for the joist tails in a suspended floor.
In best practice the Joists should sit on the DPC, & so should the air brick - but having a cavity then maybe the joist tails are protected by a lower DPC on the inner skin.
Whatever, as above,
any deck as proposed will only bring you possible difficulties.
FWIW, decks are 20yrs out of date, & are often looked on with disfavour by mortgage surveyors & some house buyers.
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Advanceddamp
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Where is our damp proof course?
It would be a good idea for you to contact a damp surveyor before going ahead with the works. You can get a better idea moving forward as to what heights are recommended