Padstone profile not square when turned on edge

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Keeping this very basic and ignoring sizes, spans, loads etc which have all been agreed by an SE and BCO. I have one simple question that is bugging me ..... should a padstone be square? If you look at the picture below, the padstone when used in diagram A is fine even though it is not square, however when turned on its edge and used on a single pier the profile of the padstone no longer makes sense as it slopes and the mortar would need to compensate for this. Is this normal or do padstones come in different profiles dependent on which orientation they are used in? It seems common sense to me that a padstone as used in diagram B should be perfectly square.

Hope this makes sense! I'll ask the SE in the morning but it's going to bug me all night if I don't clear this up now!

Cheers


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You would NOT use a padstone as in configuration B.

For one thing, the mortar bed below the padstone would be uneven and unreliable, and also the beam would not sit evenly on top.

(before you say that you can pack mortar between the underside of the beam and the padstone, you're not supposed to do that; the beam should sit on the pad without anything interposed).
 
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Fine, thought it was a bit odd. So the likelihood is that when my SE said I needed a 440x215x100 padstone, she was actually referring to a 440x215x100 HDC block performing the role of a padstone and not an actual padstone? The HDC block also has the added bonus of being square!

You may have noticed I'm still in the learning stage!
 
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If the beam is not too heavily loaded, you could use a standard 7N block.

But the best material for padstones are concrete lintels. These are 140 deep x 100 thick, and many people get short ones cut to whatever length you need.

The advantage is that the concrete is properly vibrated and cured (and therefore very dense, giving it high strength) and also has the high-tensile steel wires in it. If using a standard block, ensure there are no cracks in it.
 
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That is not a padstone.
Padstone should be square all round.
The profile you have shown is a section of a composite prestressed lintel.
Regards oldun
 
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Spoke to SE and she said she did mean a concrete block at 7N. But we'd already bought a couple of 10.5N so she said we can use them no probs. It would have been a lot easier to trim a 140x100 lintel. Out of interest do you fellas submit your own calcs to BC, or do you do the work and then get SE to do calcs based on the method to show that it is acceptable or do the BC simply look at it and sign it off themselves without calcs?
 

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