Green Building Forum - Low carbon concrete grades & availabity Tue, 19 Dec 2023 07:56:32 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=292989#Comment_292989 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=292989#Comment_292989 Tue, 09 Nov 2021 20:13:36 +0000 jms452 Is it readily available from standard suppliers?
How low-carbon can you go?
Is low-carbon just partial cement replacement with GGBFS or PFA (both of which have limitations) or is there anything better out there?
Are the low carbon versions more expensive & if so by how much?

Thanks in advance

John]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=292991#Comment_292991 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=292991#Comment_292991 Tue, 09 Nov 2021 20:48:47 +0000 djh https://www.easternconcrete.co.uk/ who happen to have their head office in Stowmarket and who also seem to have a depot in Cambridge. They do mix-on-site, which we got, so there's no waste. They were contracted by our groundworkers/foundation builders (Mead https://www.meadplantandgrab.co.uk/ ) and Michael was very keen on the eco-nature of our project. I believe it was a GGBS mix but I'm no expert in the specifics. Mead were on a fixed price contract so I don't know the concrete cost.]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293013#Comment_293013 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293013#Comment_293013 Wed, 10 Nov 2021 19:24:43 +0000 jms452
Did you ask for low carbon concrete or did they offer it?

You probably don't have these but just in case...:
Was there a spec in either carbon intensity or GGBS/cement quantity?
Was it called CemFree any any chance?

Thanks

J]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293017#Comment_293017 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293017#Comment_293017 Wed, 10 Nov 2021 20:08:46 +0000 djh Posted By: jms452Did you ask for low carbon concrete or did they offer it?

You probably don't have these but just in case...:
Was there a spec in either carbon intensity or GGBS/cement quantity?
Was it called CemFree any any chance?
I'm afraid the answer to all three questions is 'sorry I don't remember' !]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293025#Comment_293025 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293025#Comment_293025 Thu, 11 Nov 2021 08:19:19 +0000 jms452 Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293032#Comment_293032 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293032#Comment_293032 Thu, 11 Nov 2021 12:01:52 +0000 Doubting_Thomas
Depending on use you can also look into void former solutions for things like floors ( e.g. BubbleDeck) which physically displace the concrete, but I think options are more limited for foundations.]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293040#Comment_293040 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293040#Comment_293040 Fri, 12 Nov 2021 01:27:04 +0000 djh Posted By: Doubting_ThomasDepending on use you can also look into void former solutions for things like floors ( e.g. BubbleDeck) which physically displace the concrete, but I think options are more limited for foundations.
Our slab has quite a complicated shape underneath. There's a flat slab 150 mm deep and on the underside there are strengthening ribs another 100 mm deep spaced 1200 mm (one sheet of EPS) apart. I believe that's designed to allow a thinner slab that's still sufficiently strong, so as to minimise the amount of concrete and rebar. A bit like BubbleDeck and suchlike do.]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293079#Comment_293079 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293079#Comment_293079 Sat, 13 Nov 2021 10:37:46 +0000 jms452 Posted By: djhOur slab has quite a complicated shape underneath. There's a flat slab 150 mm deep and on the underside there are strengthening ribs another 100 mm deep spaced 1200 mm (one sheet of EPS) apart. I believe that's designed to allow a thinner slab that's still sufficiently strong, so as to minimise the amount of concrete and rebar. A bit like BubbleDeck and suchlike do.

That's very cool Dave - As far as you are aware is this a carbon reduction measure or typical practice?

Q for everyone:
There seem to be lots of established methods of reducing the CO2 emissions from concrete elements out there.
How widely used are these on real projects?]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293081#Comment_293081 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293081#Comment_293081 Sat, 13 Nov 2021 12:31:46 +0000 Mike1 Posted By: jms452There seem to be lots of established methods of reducing the CO2 emissions from concrete elements out there.
How widely used are these on real projects?I saw that HS2 was planning to use reduced carbon concrete, so presumably others are too...]]> Low carbon concrete grades & availabity http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293082#Comment_293082 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17278&Focus=293082#Comment_293082 Sat, 13 Nov 2021 12:45:26 +0000 djh Posted By: jms452As far as you are aware is this a carbon reduction measure or typical practice?As I remember it's to reduce the amount of concrete, both for carbon and cost reasons. The slab was originally going to be 100 mm but had to be increased to 150 mm to meet NHBC guidelines. I don't know how widespread the idea is.

There seem to be lots of established methods of reducing the CO2 emissions from concrete elements out there.
How widely used are these on real projects?
I think they're becoming quite widely used especially by any project trying to meet one of the 'project excellence' rating schemes. But whether they've made it to e.g. large housing estates yet, I've no idea.]]>