Floor ventilation / Rising damp

zeitgeist · Post by **zeitgeist** » Fri Jul 06, 2007 10:11 am

Hi all

I have two questions about my property and hope you can hep.

VENTILATION: I have noticed that my nextdoor neighbour's house has 3 vent/air bricks in the front along the bottom of her terrace house. Unlike my neighbour, however, I have a patio and I can't see any vent bricks in the brickwork below the slabs.

Will it help if I replace some of the whole bricks with vent bricks? Or could the previous owner have done something that I haven't noticed to help ventilation?

RISING DAMP: The previous owner built brick troughs along my neighbour's boundary and adjoining the wall our property. Could this give rise to rising damp, since I would guess the brickwork is higher than the damp proof membrane. Incidentally, it's hard to tell where the membrane is!!

Thanks in advance

ZG

Post by **ultimatehandyman** » Fri Jul 06, 2007 10:45 am

zeitgeist wrote:Hi all

I have two questions about my property and hope you can hep.

VENTILATION: I have noticed that my nextdoor neighbour's house has 3 vent/air bricks in the front along the bottom of her terrace house. Unlike my neighbour, however, I have a patio and I can't see any vent bricks in the brickwork below the slabs.

Will it help if I replace some of the whole bricks with vent bricks? Or could the previous owner have done something that I haven't noticed to help ventilation?

RISING DAMP: The previous owner built brick troughs along my neighbour's boundary and adjoining the wall our property. Could this give rise to rising damp, since I would guess the brickwork is higher than the damp proof membrane. Incidentally, it's hard to tell where the membrane is!!

Thanks in advance

ZG

VENTILATION:

The air bricks could be for venting underneath a wooden floor, do you have wooden floors or solid floors?

Is the property made from brick and does it have a cavity?

RISING DAMP:

How old is the property?

Many older properties do not have a DPC, but anything that raises the floor level on the outside of the property is not such a good idea!

zeitgeist · Post by **zeitgeist** » Sat Jul 07, 2007 9:35 am

Hi UHM

Thanks for your reply.

I have wooden floor. So, do you think I should go ahead with replacing with air bricks some of the whole bricks supporting the slabs?

The wall is concrete with plasterboards fixed to it via battens.

By the way, where can I get info about the houseplan. I've tried my local council but to no avail.

Cheers

ZG

Post by **ultimatehandyman** » Sat Jul 07, 2007 11:01 am

If you have wooden floors then you should have air bricks or else the timbers will eventually rot.

is there any evidence of rising damp at the moment?

Not sure if you will be able to get an house plan as I have never seen one

zeitgeist · Post by **zeitgeist** » Mon Jul 09, 2007 2:45 pm

Hi UHM

I meant to say I have floorboards with carpet on top in the living room and laminated flooring in the kitchen/dining room.

The kitchen and dining rooms are adjacent - open plan. The floor is lower in the dining room the in the kitchen,and the dining room floor dips a fair towards the external wall.

My concern is maybe the above and lack of ventilation is all inter-related.

The house is just over 25 years old.

Cheers

ZG

Post by **ultimatehandyman** » Tue Jul 10, 2007 7:12 am

An house of that age will almost certainly have a mechanincal DPC, either a DPC membrane or a couple of courses of engineering brick. There should still be some air briks though for underfloor ventillation!

leebwk · Post by **leebwk** » Tue Jul 10, 2007 11:27 am

Hi Zeitgeist,

Basically you should have a minimum of 150mm (2 courses of bricks) from your ground level to your dpc level anything less than this could cause a problem in the future, also if you have hollow floor construction you should have air-bricks front and back to promote air flow and through air.
As UHM as stated a house of that age should have all necessary dpc's in place, if you can't find any air bricks or they have been covered up then i would make sure you have them installed or uncovered, you really need at least 3 front and back.
Hope this helps

zeitgeist · Post by **zeitgeist** » Wed Jul 11, 2007 10:15 am

Hi Leebwk

Thanks for your advice. I'll go ahead and replace some of the patio bricks with air bricks.

Cheers

ZG

zeitgeist · Post by **zeitgeist** » Tue Jul 17, 2007 9:02 am

Hi guys

I bought some air bricks to fit under the patio but I'm having second thoughts.

Now, I'm thinking, maybe instead, I should fit the type of bricks with the 3 big holes and little ones so that more air can reach the wall with the original air-bricks - I dont know what state those are in.

Your thoughts and advice would be appreciated.

ZG

jamino · Post by **jamino** » Thu Jul 19, 2007 10:22 pm

modern guidelines for suspended timber floor, require ventillation to be availaiable every 600mm, just a guide for you m8.,

zeitgeist · Post by **zeitgeist** » Mon Jul 23, 2007 6:57 am

Hey, thanks Jamino. I thought it had to be every 2 metres.

I went to the dump to throw away some rubble and saw some bricks with 10 big round holes.

I was wondering if I used these instead of the airbricks with 18 square holes, then more ventilation would be available. But, I'm concerned about mice getting through under the patio.

What do you guys think? Thanks

ZG

jamino · Post by **jamino** » Mon Jul 23, 2007 9:27 pm

ventilation is ventilation m8, the cosmetic issue is up too you!

Floor ventilation / Rising damp

Floor ventilation / Rising damp

Re: Floor ventilation / Rising damp

Floor Ventilation - part 2