Cavity Wall Construction

Post by **Big Boy** » Thu Jan 18, 2007 3:39 am

lockwood74,

Is this what you meant?

You didn't need the ?v=0 at the end.

I've made it work for you, but I haven't got a clue what its all about

Post by **lockwood74** » Thu Jan 18, 2007 3:49 am

Thankyou for the assistance with the photo.

I am keen to explain the photo as well !!!!!

I have used cavity wall construction in my house. I am using cavity walls of 200 - 250 mm thick in construction. Although the house is not complete yet, I am hoping that it will provide a cooler house in the heat of the summer.

I have not seen this type of construction in Thailand and am not sure why.

It does have disadvantages, in that it reduces the size of the house internally by taking up so much extra space. Im hoping the advantages will out weigh the disadvantages.

In covering up the columns and cutting down on energy bills to cool the house.

I have managed to check the exterior of the wall in full sun and it gets very hot, however the internal wall remains much cooler.

the true test will be when the house is complete and in the summer months.

I am surprised that even properties of 10 million plus are using single skin walls of 100mm thick.

I am looking forward to the finished house to report on the end result

Regards John

Post by **Big Boy** » Thu Jan 18, 2007 4:08 am

Thanks for the explanation - a bit technical for me. However, I'm sure somebody with a lot more knowledge than me will offer an opinion.

Just out of interest, there was a similar thread that dragged on for some time on here a while back http://www.huahinafterdark.com/forum/vi ... php?t=2935 - just thought it might be of interest.

Post by **dr dave soul monsta** » Thu Jan 18, 2007 7:39 am

There are A few of th European developers using insulated cavity features.
addition of air bricks around the base of the wall would allow cooler air to flow through the cavity but i would imagine there would need to be additional ventilation in the roof space to create the desired draft effect ..

Post by **JimboPSM** » Thu Jan 18, 2007 8:18 am

Not trying to put a dampener on this, but just wondering whether you need to use any insect repellents or do anything to seal the cavities to prevent the local critters taking refuge and claiming squattersâ€™ rights.

In many buildings in Thailand armies of ants appear to emerge out of joints and the smallest of cracks or splits in brick, plasterwork etc.

Iâ€™ve used â€œant chalkâ€

Post by **Nomad** » Thu Jan 18, 2007 8:55 am

Walls are only one way your home gains heat. Double walls are an acepted part of Thai building. This technique will produce good results for cooling as well as other reasons. The finished walls are nicer to the eye because you end up with a smooth wall and no support columns bulging out from the corners or walls. It is also a very good sound barrier as well as keeps the dust and other polluants out. We build the walls closer together than your picture. This is only one part of the puzzle. You have opened the cookie jar. If you really want to go for it, you need to go to Hua Hin Glass and buy double glazed windows and make sure they are siliconed in right. Temperature loss occurs in the celing which you now need to insulate properly, so you need to put in 4 to 8 inches of fiberglass or other suitable materials. Then, check your electirical fitting and seal them up. Now you need a good quality door set and make sure that it if fitted properly with a door sweep. There are a few other things too but now you have it pretty well there. Is it worth the extra cost? Maybe if your house is in an noisy area of town.

Post by **JimmyGreaves** » Thu Jan 18, 2007 9:18 am

Don't know to much about construction. But used to see wall ties inside the cavity to strengthen I think. Are these no longer required?

Where is the house situated as I wouldn't mind taking a look for when I eventually start the process.

Post by **Rob W** » Thu Jan 18, 2007 2:04 pm

I would use wall ties to link each wall togeather. the other thing to watch is closing the cavities at each opening ie windows and doors, you can buy in the Uk stuff called "cavity closer " but i doubt it will be available in Thailand. guess youll have to improvise.
I was told to insulate the cavity with rockwool or what ever is available locally.
Not sure about insect infestation but I would guess a fine mesh grill at the airbricks would be needed.
I looked at using this method for my place but desided on letting them build as they are used to if im not there permanently to supervise them.
I had enough trouble with the builders on the house ive built in the UK!!
when wanting something slightly differant from the norm.

Rob

Post by **Guess** » Thu Jan 18, 2007 4:02 pm

Another couple of trick I have seen in use but do not know if either are cost effective.

1. Use reflective insulation in the cavity with the reflection pointing outwards.

2. Fit small plastic pipes in between the outer brick wall bricks every meter or so. If you then get infested wit ants the spray with the plastic tube attachment can be interested and kill all the vermin.

I have only seen reference to keeping the house cool. When you have acclimatized to the local weather you will definitely at some point be wishing you had fitted central heating. WE had about one month of very cold nights last year and at lest one week nearly as bad this year.

Even tourists were wearing jackets.

Post by **malcolminthemiddle** » Thu Jan 18, 2007 5:20 pm

JimmyGreaves wrote:Don't know to much about construction. But used to see wall ties inside the cavity to strengthen I think. Are these no longer required?

Where is the house situated as I wouldn't mind taking a look for when I eventually start the process.

The prime function of UK type cavity wall ties is not to provide structural stability but to prevent the movement of moisture between the two skins. Remember the butterfly type? The twist in the centre is designed exactly for that purpose.

Post by **JimmyGreaves** » Thu Jan 18, 2007 7:11 pm

malcolminthemiddle wrote: The prime function of UK type cavity wall ties is not to provide structural stability but to prevent the movement of moisture between the two skins. Remember the butterfly type? The twist in the centre is designed exactly for that purpose.

Yes it's all coming back to me now, the butterfly type. I used to work in a builders merchants for a short time.

Post by **STEVE G** » Thu Jan 18, 2007 7:37 pm

Lockwood, your cavity wall looks surprisingly neat for Thai construction. A friend of mine is currently having a house built with the Q-con bricks that were mentioned in an earlier thread; these also give a smooth wall line and are supposed to insulate against the heat. It would be interesting to compare the relative costs and insulating performance of these two types of construction.
As to wall ties, I imagine they would not be required for the type of construction you are using as the walls are not load bearing, but Iâ€™m only guessing as Iâ€™m an aircraft engineer and not a civil one!

Post by **Onlyme** » Thu Jan 18, 2007 9:32 pm

A good friend of mine recently completed building a house for another friend. The quality of workmanship was outstanding. This was his second project, the first house was built for himself. He managed to sort the "wheat" from the "chaff" on the first house and has a good crew working for him.
PS. Don't forget to use a good loft insulation.

Post by **higgy** » Fri Jan 19, 2007 9:13 am

I have found a very good informative site regarding building materials to use when building in Thailand.It,s called "The ex pats builders guide" and is well worth a look.It is quite detailed and covers many areas such as
building materials,roofs,plumbing,electrical, concrete and much more even estimated costs of things like bricks etc.
http://www.coolthaihouse.com/
It has certainly given me some help.

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