Which Beam & Block systems include hollow blocks in their span chart listing

[Boyblue]

100mm solid blocks are not available here so I've been looking at importing the beams and using hollow (three hole) blocks.  One of the first companies I looked at had the 3.6n category. Now that I'm trying to choose from the available options, I notice there aren't many.  I'm concerned about being in the minority here.  Are hollow blocks less than ideal, inefficient or ineffective?

[nod]

I’ve never heard of hollow blocks being used Which might be due to the easy availability of solids here Id check with your beam supplier 

[Alan Ambrose]

The blocks are partly taking the loading from people, furniture etc, so that’s probably the reason that solid blocks are assumed. I suppose, in a pinch, you might fill some hollow blocks with concrete - but you would be fairly off piste from the manufacturer’s designs.

[Nickfromwales]

8 minutes ago, Alan Ambrose said:

The blocks are partly taking the loading from people, furniture etc, so that’s probably the reason that solid blocks are assumed. I suppose, in a pinch, you might fill some hollow blocks with concrete - but you would be fairly off piste from the manufacturer’s designs.

Have you not considered BeamShield or other insulation block system vs concrete blocks? 
Light, huge improvement over cold blocks, and a 1 man fit for DIY. 
Doubt I’d ever do a block and beam floor any other way, just seems madness to make an awfully cold foundation and then pay to cover it with insulation to mitigate  

[Alan Ambrose]

>>> Beamshield

 

Huh, interesting. Jeez their website is hard work, a labelled drawing would help.

 

So, the usual blocks are replaced by formed EPS? What provides the structural strength? Oh, I see ‘“and a layer on which to lay the structural concrete topping”.

 

So, you cast a normalish slab on top? How thick typically? Presumably the EPS supports the wet load without any further propping? Reinforcing? If you’re doing UFH, do you use an additional screed or try to do it in the concrete and powerfloat?

[Mr Punter]

16 minutes ago, Alan Ambrose said:

So, you cast a normalish slab on top? How thick typically? Presumably the EPS supports the wet load without any further propping? Reinforcing? If you’re doing UFH, do you use an additional screed or try to do it in the concrete and powerfloat?

 

It is a concrete screed 50-75mm thick with light mesh.  You can use fibres instead but no point as it makes it harder work.  If you lay it well you can tile straight onto it.

[Nickfromwales]

1 hour ago, Alan Ambrose said:

>>> Beamshield

 

Huh, interesting. Jeez their website is hard work, a labelled drawing would help.

 

So, the usual blocks are replaced by formed EPS? What provides the structural strength? Oh, I see ‘“and a layer on which to lay the structural concrete topping”.

 

So, you cast a normalish slab on top? How thick typically? Presumably the EPS supports the wet load without any further propping? Reinforcing? If you’re doing UFH, do you use an additional screed or try to do it in the concrete and powerfloat?

If it’s a decent airtight house with UFH, then during the heating season you’d be ‘on constant’ (long and low) so having a decent slab would be beneficial. 
I’d recommend around 80mm of liquid Cemfloor, but you could go thinner. 
B&B floors should be designed so parallel load bearing walls land on a single or (sistered) pair of beams, depending on the type of load etc.