engineering or standard bricks?

[mayday]

We are just about to start our new build house, the builder is supplying labour and us the materials. Foundations are due to start in

2 weeks, builder has asked for a small qty of bricks to edge the raft foundations to 3 courses(to damp). I have seem these done in engineering bricks on sites before, with standard finishing bricks on top, I have also seen standard facing bricks all the way down.... Aesthetically it surely looks better if the bricks are all the same, so I'm guessing this has something to do with the strength and other qualities of the engineering bricks? If this is the case why is it optional... my architect and LA regs haven't mentioned them?

Thanks.

[Roger Mills]

You need at least semi-engineering bricks below the DPC. Ordinary bricks will soak up moisture and be prone to frost damage.

[The Natural Philosopher]

To some extent you can alleviate that by giving the bricks a waterproof coat below ground, but I would not bet on it.

A lot depends on where you are and where your wall is. North facing walls in frost hollows in the North? forget it. Darn Sarf with a sheltered location near the coast. Probably unlikely to ever get a good frosting.

Consider concrete blocks up to damp level, at least on the inner side of a double wall. Cheap and tough.

[Dorothy Bradbury]

To edge the raft, below floor level, I would use engineering. o Standard blow off in hard frost, damp, in sheltered area o Standard blow off if any roof/guttering leak in a hard frost

I know the latter from experience and Warrington imbeciles who fitting guttering with more leaks than it had originally.

If you have to replace a brick it involves Armeg chisel each one out, mortar in a new, one by one, over a period of time.

Concrete block is probably acceptable, but are engineering that much more for 3 courses - it should bluntly be bugger all cost compared to the price of a raft (which is vastly more).

Standard bricks can be as porous as a sponge.

[mayday]

Thanks to all who responded, makes sense, I think I'll go with engineering bricks!

[Rick Hughes]

I have built 3 houses, never been required by Bld regs to use engineering or semi-engineering below DPC. While going through college worked on a building site every holiday .. and that means dozens of houses - again none of them required engineering bricks.

Below ground level may be a different matter ... but in my part of the world same bricks used below DPC as above it, on all above ground work.

[R]

Concrete

[Phil]

Check prices if I were you - eng bricks are often cheaper than pretty facing bricks. Use a stronger mortar mix that is less 'wet' or they'll float around, less suction see 'cos the are less porous.

Phil.