looking at houses, they all have cracks in the walls. Why?

[Junkyarddog]

Awk,

Here is the reason.

First of all houses and shophouses in Thailand are not built on a floating slabs as we do in the USA. We build on piling here. Every concrete wall in this country has expansion cracks. It is not so much as the rendering did not go well or any of that sort of thing. Every building from a small house to a skyscraper is constantly moving. As we all know heat causes expansion and cold causes things to contract. Air con effects a house. In a office building if you go into one at midnight after the air has been turned off a few hours and if its quite, you can actually hear the building moving. Concrete walls here have no expansion joints or construction joints as they are sometimes called. So when the house or building wants to move, something has got to give somewhere to allow that small amount of movement. Hence a crack shows up in your wall. This is absolutely normal here and there is nothing that can be done about it short of installing a expansion joint in the wall. That crack is where the house or building has decided it's going to give a little bit. Don't worry about it and as you may have noticed everyone who has replied has the same problem. These cracked walls do not indicate there is a structual problem with the building. Don't try to fix them either, the building is going to give there and you can't stop it. If you grind out the crack and refill with what ever material you wish to use refinish and paint, guess what? The crack will be back next week.

[MichaelJohn]

I think most structures here a based on pillars and beams. The walls are only in-fill offering no structural purpose. The cracks in the in-fill walls and/or plaster are normal as the house drys and moves slightly.

Any cracks in pillars/beams should be considered of concern,

[alfieconn]

During ground works if the ground is not compacted and/or doesn't have a decent ground water course then the weight of the building and/or the ground washing away will make the building settle. If you look at the pavements and roads here they are just placed on the surface or, at best, sand. This is why they disintegrate so quickly. Yes, it's cheaper in the beginning but the "whole life cost" is much more expensive.

Sorry but I'm not a builder so this might be a stupid question, but when you say "the ground is not compacted" do you mean the ground that the pads sit on ?

Sorry, I'm not sure what you mean by pads. I'm going to guess we're talking about pavements here and pavement slabs (that's what we call them in England anyway). Yes. In England (and many other countries) pavements and roads are built by first removing a layer of dirt which you replace with crushed rubble/aggregate. This is compacted down using a compactor (a large plate attached to a machine that bangs up and down). This will be moved over the surface slowly to make sure it is pushed down so the lumps of hardcore are in a position where they can't move. Sometimes this is filled with sand as well which is then compacted down too. Finally you are ready to pour cement, smooth that down and then lay paving slabs. This technique allows for water to pass underneath the cement and run off into the ground whilst ensuring no holes are made. This technique means that pavements in England (which receive a tremendous amount of foot fall but no motorbikes, cars, etc) last for a LONG time. Living in the same house for 20 years growing up I can't remember seeing the pavements being replaced once in my street or village.

This is a more complex version

Here is a page on laying driveways and paths using bitumen

http://www.pavingexpert.com/tarmac02.htm

Hope this helps.

Sorry to take you to task, but the diagram shows concrete only being used to secure the kerbs. Not to lay slabs upon, a strange practice that I have only ever seen in England. If you can lay and smooth out concrete of a decent quality you don't need slabs, do you?

Well my question did ask about "if the ground is compacted" which was related to buildings, the pads (slabs) I refer to are the concrete base which each column sits on.

Edited November 18, 2014 by alfieconn

[KhnomKhnom]

YES, it is very likely a bad problem that will progress to worse. I watched a house I wanted to buy settle over two years as I haggled over it and the main crack went, with no other forces except settling, from 2mm to wide enuf to see outside thru it. It was still growing when I gave up on it.

In areas not old flood plane or silt or that stuff, like BKK, the problem is inadequate under soil preparation and, very important, also the badly installed pilings and other methods of securing the foundation. Good Thailand homes, those well built, do not depend on setting of the earth, but set on long concrete posts put deep in the earth and other extensive methods to stabilize the house against soil movement.

I saw a large, 6BR, house setting a meter or more above the earth and setting on piles alone. The house was completely solid with no cracks and all the interior doors opened/closed OK, indicating a solidly built house. It did not at all rest on the soil.

If a house is shoddily constructed, it will use the soil as part of the support and have token foundation. The soil settles, if newly laid in... like even 4 yrs ago...... and the house cracks... and WILL CONTINUE to crack likely forever.

Any house with cracks should be sold with a discount price equal to installation of new additional piles and other repairs that will inevitably come over the years. Disbelieve me at your peril.

[bkk_mike]

During ground works if the ground is not compacted and/or doesn't have a decent ground water course then the weight of the building and/or the ground washing away will make the building settle. If you look at the pavements and roads here they are just placed on the surface or, at best, sand. This is why they disintegrate so quickly. Yes, it's cheaper in the beginning but the "whole life cost" is much more expensive.

Sorry but I'm not a builder so this might be a stupid question, but when you say "the ground is not compacted" do you mean the ground that the pads sit on ?

Sorry, I'm not sure what you mean by pads. I'm going to guess we're talking about pavements here and pavement slabs (that's what we call them in England anyway). Yes. In England (and many other countries) pavements and roads are built by first removing a layer of dirt which you replace with crushed rubble/aggregate. This is compacted down using a compactor (a large plate attached to a machine that bangs up and down). This will be moved over the surface slowly to make sure it is pushed down so the lumps of hardcore are in a position where they can't move. Sometimes this is filled with sand as well which is then compacted down too. Finally you are ready to pour cement, smooth that down and then lay paving slabs. This technique allows for water to pass underneath the cement and run off into the ground whilst ensuring no holes are made. This technique means that pavements in England (which receive a tremendous amount of foot fall but no motorbikes, cars, etc) last for a LONG time. Living in the same house for 20 years growing up I can't remember seeing the pavements being replaced once in my street or village.

This is a more complex version

Here is a page on laying driveways and paths using bitumen

http://www.pavingexpert.com/tarmac02.htm

Hope this helps.

Sorry to take you to task, but the diagram shows concrete only being used to secure the kerbs. Not to lay slabs upon, a strange practice that I have only ever seen in England. If you can lay and smooth out concrete of a decent quality you don't need slabs, do you?

That's because, in the UK, most utilities are underground below the pavements, especially in cities. It's a lot easier to lift and replace slabs than to drill through concrete.

Our house in Thailand was built almost 20 years ago, and has no cracks on the original building where piles were driven into the ground for support.

We do have a couple of cracks where we extended a porch wall, and that is almost certainly where one end of the wall is being supported by the original piles, but the concrete foundation supporting the rest of the wall is presumably settling.

But that's just a porch wall, so I figure I'll just leave it a few more years (for the settling to finish) and then fill in the cracks and repaint.

Edited November 18, 2014 by bkk_mike

[buzz]

IF it's just cement render cracking, then simply by using PVA (poly vinyl adhesive) in the render mix stops any cracking ... it's easy to find and relatively cheap ... I used it on 7 Villas and almost no render cracks at all (ie: except the render where I think the labourers 'forgot' to add the PVA I'm guessing)

[khunPer]

Can be/sounds like a common render problem that many houses suffer from, often caused by render drying up too fast in Sun and/or wind, and no water proof additive to avoid cracks in the cement-and-sand mix.

Can fairly easily be filled – if done carefully the cracks may not be noticed – and then need primer and paint. If a lot, the whole wall may need a skim coat.

[montry]

Many houses; in Thailand are just floating.

This will occur; because all the construction beams are to short.

Even in bangkok they are building houses with construction beams from six meters,where they actually have to use beams from around 20 meters or more to reach the sand layer.

But don't worry; Our houses in Bangkok are floating for already 30 years and are still O.k.

Edited November 18, 2014 by montry

[Doc46]

Almost certainly settling on top of poorly compounded foundations. Have you seen the pavements and roads here?

Can you please explain a bit clearer what you mean by this statement.

During ground works if the ground is not compacted and/or doesn't have a decent ground water course then the weight of the building and/or the ground washing away will make the building settle. If you look at the pavements and roads here they are just placed on the surface or, at best, sand. This is why they disintegrate so quickly. Yes, it's cheaper in the beginning but the "whole life cost" is much more expensive.

Agreed. After 6 years here, I have yet to see a vibrating compactor. Not even in the building supply shops.

You gone to the wrong shops,,,plenty shops have compact vibrators,,,,, I know ,they say let the dirt fill settle for 3 months then you can built on that ,,it's bull crap.

[jacko45k]

Mines the same, I would think that it is just the render drying out, not dissimilar to plaster drying out in the UK ! incidently I had a pest control guy round the other day and he commented on it and said his house in Pattaya was exactly the same.

To be fair, after the recent earthquake tremors in Cm I'm surprised the cracks aren't a lot worse !

My house has cracks in the bathroom tiles.

Take a paint scraper and check they are just superficial, likely settling cracks in the plaster.

If you can see daylight through them that would be another matter.

[alfieconn]

Could also be a poor paint job. We had similar problems within the warranty period on our house and since the developer would most likely do a poor paint job once again and I had TOA to come to our house and come up with a solution. The problems were:

1. Cracked walls on the outer walls of the house itself.

2. Cracked walls on the outer/inner side of the fencing around the house including fungus.

The solution for fungus is of course anti-fungus material being appiied after the walls have been washed down completely.

The solution for the cracks on the outer walls of the house is

Elastomeric Paint Coating

http://www.hytechsales.com/prod1000.html

The walls are now OK.

I was thinking about something like for when I next paint the house, can this product be obtained in Thailand ?

[bearbkk]

I have cracks in the walls both in my house here in Thailand and in my apartment in Paris. None of which worries me. The cracks in the walls of my house are mostly cracks in the render, others originate from the corners of windows and doors, which are probably caused by moisture causing the expansion of wooden frames. All these cracks can easily be covered up with some plastering before the next time you paint. These types of cracks have no impact on the integrity of the building. In my apartment in Paris, the cracks are probably caused my settlements of the building. Still, these are very tiny cracks and when using the correct methods of plastering they can easily be covered up. Most houses in Thailand are built without any load bearing walls so cracks are only a concern if you find them on pillars or beams.

[Awk]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

[Anthony5]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

In my opinion compacting the soil has nothing to do with it, as a house in Thailand is built on footings,columns and beams that hold the construction, and can you imagine a compacted soil that doesn't drops even 1 cm over the years? So if the soil under your floor base drops 1 cm it has the same effect as a soil that drops 10 cm, e.g. there is empty space between.

Most important in a built in Thailand are the size, space, amount and depth of the footings.

[klikster]

Agreed. After 6 years here, I have yet to see a vibrating compactor. Not even in the building supply shops.

Our builder in KK used a vibrating compactor as well as a vibrating probe into the concrete columns. I have seen compactors for sale at Thai-Watsadu.

[Awk]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

In my opinion compacting the soil has nothing to do with it, as a house in Thailand is built on footings,columns and beams that hold the construction, and can you imagine a compacted soil that doesn't drops even 1 cm over the years? So if the soil under your floor base drops 1 cm it has the same effect as a soil that drops 10 cm, e.g. there is empty space between.

Most important in a built in Thailand are the size, space, amount and depth of the footings.

Thank you, that also makes sense. I assume the factors you mention would depend on various things, including not only the house that is to be built on top, but also the soil the footings are placed in? If I assume that your opinion is that many of these problems are caused by errors in the factors you mention, then I guess many of the people who create the footings do it wrong. Any tips for how to find somebody who knows how to do it correct, especially in the north/Chiang Mai area? Or is it something we can not expect in our price class (e.g., for a house that costs 2-3M to build, excluding the price of land)?

[Anthony5]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

In my opinion compacting the soil has nothing to do with it, as a house in Thailand is built on footings,columns and beams that hold the construction, and can you imagine a compacted soil that doesn't drops even 1 cm over the years? So if the soil under your floor base drops 1 cm it has the same effect as a soil that drops 10 cm, e.g. there is empty space between.

Most important in a built in Thailand are the size, space, amount and depth of the footings.

Thank you, that also makes sense. I assume the factors you mention would depend on various things, including not only the house that is to be built on top, but also the soil the footings are placed in? If I assume that your opinion is that many of these problems are caused by errors in the factors you mention, then I guess many of the people who create the footings do it wrong. Any tips for how to find somebody who knows how to do it correct, especially in the north/Chiang Mai area? Or is it something we can not expect in our price class (e.g., for a house that costs 2-3M to build, excluding the price of land)?

A qualified architect should know the size, depth and location your footings need to be. If in doubt, I'm sure Chiangmai will have a technical college who will have details about soil specifics in your area, and know how deep you should go to reach solid soil.

[casualbiker]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

In my opinion compacting the soil has nothing to do with it, as a house in Thailand is built on footings,columns and beams that hold the construction, and can you imagine a compacted soil that doesn't drops even 1 cm over the years? So if the soil under your floor base drops 1 cm it has the same effect as a soil that drops 10 cm, e.g. there is empty space between.

Most important in a built in Thailand are the size, space, amount and depth of the footings.

What holds your ground pins (piles) in place if not the compacted earth that they have been rammed through?

Different parts of Thailand require different footings / piles. Most of Bangkok and surrounding area is piled with a concrete slab on top. And in the case of my rented house, poorly done pile and slab!

[casualbiker]

Good example of the ground disappearing from under your house! This is a pile and pad house. To make things worse it's also a prefabricated concrete building (badly prefabbed)

It also has cracking in one corner that actually lets rain in or it could be the atrocious fitting of the windows.

[Anthony5]

Many thanks to all for the helpful posts.

If my understanding is correct, cracks like these are not a serious problem as the walls are not intended to carry load. It is mostly expected here, but can to some extent be avoided if the house is built properly, perhaps particularly with regards to compacting the ground firmly before laying the foundation.

In my opinion compacting the soil has nothing to do with it, as a house in Thailand is built on footings,columns and beams that hold the construction, and can you imagine a compacted soil that doesn't drops even 1 cm over the years? So if the soil under your floor base drops 1 cm it has the same effect as a soil that drops 10 cm, e.g. there is empty space between.

Most important in a built in Thailand are the size, space, amount and depth of the footings.

What holds your ground pins (piles) in place if not the compacted earth that they have been rammed through?

Different parts of Thailand require different footings / piles. Most of Bangkok and surrounding area is piled with a concrete slab on top. And in the case of my rented house, poorly done pile and slab!

Most areas in Thailand don't need piling, that is unless it is recently filled land or a swamp like rice fields or like Bangkok is.

Footings are placed on solid soil about 1 to 1,5 meter below surface depending on the kind of soil, are in most instances at least 1 meter in diameter or more, and of course are connected with each other by a concrete beam and concrete floor base.

[kamalabob2]

You can speak English to the technical representatives of Lanko Building products for the next four days at the Buriram Home Expo. Lanko has on offer some worthwhile products to prevent cracks and to seal with cracks after the fact.

[damo]

Has anyone seen Lime used in solid render in Thailand?

Walls primed with water & PVA prior to rendering?

Sufficient mesh, reo?

Expansion / Movement joints?

Slabs sealed (fortecon plastic sheet) prior to pour?

Priming walls with PVA mixed with water will increase the bond, Lime will improve the workability and make the render much more water proof. Both will increase flex and reduce the likelihood of cracking and becoming drummy.

Larger cracks can be minimised with better reinforcing / bracing and better concrete. I would prefer 35mpa minimum in my next house, for piers and rafters.

Subsidence is predictable and preventable, not building with excessive weight, compaction, using fortecon, allowing the site to settle.

Movement joints, brick ties, damp courses, better mortar, better materials (cinder blocks are shit) etc,etc. There is so much missing from a Thai builds that can improve the life span and enjoyment of the home. IMO a lot of it is lack of knowledge of products / materials and practices.

[rocketboybkk]

If it just the render then it's eager to fix.

It's it's cracked all the way through then it's not good.

Subsidence is costly & a risk.

Probably the render as said but I agree it looks unsightly

Sent from my iPhone using Tapatalk

[IMHO]

If using the correct render mix, and the walls are true enough to allow <=2cm render thickness, you shouldn't get cracks.

Generally speaking, cracks are a sign of poor brickwork, or low grade/incorrect materials.

Premixed rendering mortar (just add water) is readily available and cheap - no reason not to use it.