Building Blocks Or Engineering Bricks For Underground?

[Tozzy]

Before I start making a visual plan for my underground room project, I need to know if it would be ok to use breeze blocks for the underground structure or if it would strictly require engineering bricks. I would of course be tanking the walls and stuff once built anyway and I would rather use breeze blocks as the laying will be easier and I would imagine far cheaper. What do you think? Breeze blocks all the way?

Oh and do you think that lining the other side of the walls (the walls that go against the soil) with DPM would be a good idea?

Cheerz

 

[Tozzy]

Sorry guys, I realise now it's a silly question because obviously, engineering bricks will be too expensive lol. I don't know what I was thinking. lol I shouldn't worry too much because I just found out that 'Dan Price - The Man In A Hole' lined his with just treated wood! Don't think he did any proper damp proofing.

Anyway, I'll go with the breeze block method and do a plan of it.

I presume the standard size for breeze blocks are 440mm x 220mm x 220mm.

 

[freddiemercurystwin]

The reason no-one's replied to your post is because (with all due respect) you sound like your embarking upon something that you don't seem to know much about. By breeze blocks presumably you mean high density concrete blocks which are 100x215x440 by the way. Are you doing this with building regs?

 

[Tozzy]

The reason no-one's replied to your post is because (with all due respect) you sound like your embarking upon something that you don't seem to know much about.

I agree with you, but I do have an idea of what I need to do. If I see everything laid out exactly on a 3d plan (which I can do because I've done 3d modelling work before), I'm confident I can copy what I see. I'm not just going to do this as I go along.

About the building blocks, none of my books cover this building material (only bricks) so this is why I needed some info on it.

I hope people don't think I aim to build something like this:

But more like something like this:

Basically, I'm just digging a huge hole, putting up some walls (I can learn how to do this from my DVDs etc) and incorporating a roof into the finished structure to hold up some thin slabs for my little patio . I've done much harder things than this believe me lol.

Are you doing this with building regs?

Why would my little 6 foot secret hut under the ground need to conform to building regulations lol ?

Thanks for your info on the building blocks. This means I can get cracking on the 3d plan.

 

[JohnD]

reinforced concrete is what you need. Ground pressure can be very high (especially after rain) and the sides may cave in.

You can avoid building regs and Planning Permission if what you are building is a domestic Fallout Shelter. Floor area less that 30m2. Distance from nearest building greater than depth of excavation.

 

[Tozzy]

reinforced concrete is what you need.

Got a great idea then in that case! There is a neighbour down the road from me and he has used reinforcing Rods that stick up out of a bed of concrete that holds up the bank. Then they just put the blocks through the rods using the holes that they have at the top of them. They've nearly finished it and it looks great and will do the job of acting as a retaining wall. I think I will do the same.

Thanks for that info JohnD. Oh and yes it will be a fallout shelter for when world war 3 breaks out .

 

[freddiemercurystwin]

Ground pressure can be very high (especially after rain) and the sides may cave in.

No need to worry about little things like ground pressure JohnD, after all;

I can learn how to do this from my DVDs etc)

 

[Tozzy]

Actually I think something is wrong. Building blocks don't have holes, breeze blocks do so these must be breeze blocks on this picture:

Otherwise, how am I supposed to slide them through the rods?! That in the picture is exactly what I need. I just need the dimensions of a standard breeze block.

 

[JohnD]

"Breeze" blocks, made of furnace waste, have not been made in the UK for at least 30 years.

You can get hollow concrete blocks, including tri-wall blocks which have webs inside for extra strength and stiffness. After you have threaded them down the rods you have to fill them with concrete. remember you will need lateral reinforcement, not just vertical.

It is also possible to build two brick or block walls, with steel mesh between, and fill the cavity with concrete once a day before building the next course.

there is also a method of building brick walls in "shelter bond" with steel rods laid between the bricks.

For your underground chamber, I still think you would do better with reinforced concrete, probably using welded mesh rather than rods. The waterproof layer has to go on the outside surface.