Annker

Yes, typically they all quote D50 and some then quote a few other common DT's. But regardless I compared all against D50

Thanks John, that makes sense.

Hi Gus, To my mind this is not the issue, as I am comparing one cast iron radiator section against another. I called CIRC and as expected they can't give a specific reason why their section is upwards of 25% more efficient than all others, but they can say that no customer has raised this issue before. Is it just my experience or do the majority of building product suppliers in the UK seem clueless about their products. Anyway, as you also suggest I think if I use CIRC it is wise to oversize. My AI assistant summarises as such: Bottom line: With an ASHP, the risk profile is asymmetric. Undersized radiators force higher flow temperatures and reduce efficiency. Oversized radiators allow lower flow temperatures and improve efficiency. If you must err, err on the side of larger. Sizing to Paladin/Carron figures while buying from CIRC is a sensible, low-risk strategy. Worst case: you've got slightly more efficient heating and spent a bit more on radiators. Best case: you've sized correctly.

I've also noticed that CIRC state that a 4 column 760x1310 has an output of 2400W; where as their 3 column 745x1310 has an output of 2403W. A smaller section with one less column having a greater(albeit slightly) output surely cannot be correct or am I missing something?

Adds a bit more context that the Cast iron radiator centre are claiming that their 745mm high 3 column section has greater output than the Stelrad 760mm high 4 column section. It just doesn't seem likely to me. The thing is that CIRC seem to be a lot less expensive than all other suppliers, even if in reality you need to size up from their performance tables. I just want to make sure I get genuine performance figures from them.

Well that's what I'm assuming also; that is given that the designs, or material used are not significantly different, the outputs should be more or less the same. So the question is whether 4/5 brands are understating the performance of their product or one brand is overstating their performance. The latter seems more likely. AI suggested that I request their BS EN 442 test documentation to verify the claim output. I will do that tomorrow and imagine more than likely be met with silence.

I'm looking to buy cast iron radiators to install downstairs in a victorian renovation. Cast iron radiator centre are a supplier that seem to be competitively priced, if not one of the cheapest suppliers on the market. A potential catch which I am trying to resolve is the accuracy of their claimed performance (watts). I asked AI to compile a table and it illustrates as I thought, that CIRC claim their sections put out ~25% to 30% more heat than most other brands. As these sections are pretty much the same design, and I imagine are produced from same material, across all brands it seem like a claim worth verifying. Has anyone ever had the similar query? The heating system will be ASHP so I'm keen to match the respective heat loss figures for each room accurately and Obviously I don't want to end up with undersized rads. . 3-Column Cast Iron Radiator Output Comparison (~745-750mm Height) Per-Section Output @ ΔT50 Manufacturer Model Height Watts/Section Cast Iron Radiator Centre (CIRC) Traditional Victorian 3-Col 745mm 115W Shelbourne (CI Radiators 4u) 3-Column 745mm 86W Paladin Victoriana 3-Col 745mm 86W Arroll Neo-Classic 750 745mm 92W Carron Victorian 3-Col 745mm 80W

Interesting, I wasn't aware such slim lights were available. I should have clearer that I have a somewhat specific light design intent, wrt downlighters I want trimless, small diameter and in some instances directional. For what I have seen ticking them boxes means a fitting with a min depth of ~90mm As aside on a previous project I worked with John Cullen Lighting, they were client appointed and initially I thought Lighting design was a makey uppy discipline to extract money out of wealthy home builders but I learnt a lot from them and a good lighting design certainly elevates a project to the high end.

Its a retro fit/renovation. I think it would be near impossible to seal the perimeter of the VCL if it was fitted above the joists, and also more difficulty to fit the insulation to be laid between the joists. Photo below for reference, as you can see its very easy for me to fit the vcl from below. I have a thread going on IWI, my design was largely gathered from very useful info received on the forum and I will updated it once that phase of works is complete

Yes this is a good solution for me, fully constructed boxes probably aren't necessary just need some bit of background to taped the vcl to

Have you a link to lights that small, sounds like a great option if required. I'm afraid shallowest light I'm using is ~90mm

In summary I am fitting an intello plus AVCL to 1st floor ceiling joists, these rooms will have downlights fitted in the ceiling which are about 120mm in length. I cannot create a service void below the AVCL to accommodate the downlights, therefore they will be located within the ceiling joist void, hence above the level of the AVCL. There is an off the shelf solution like these however I do not see any mention of them being used by builders on this forum. I am a carpenter so I could make plywood boxes into which the AVCL is folded up into. I'm sure this must be a common detail but I can't find much detail on solutions so keen to hear what others have done to maintain the air tight layer in this situation.

@ProDave Hopefully the manufacturers have considered that but I guess only practical "testing" will confirm. My initial plan was to run the horizontal soil from the frame at/above floor level; as opposed to below floor level within the joist void. Therefore avoiding any rearrangement of the joist solid bridging. However, from the image of the frame I noticed that the short vertical outlet attached to the frame appears longer than those on say Geberit frames. Rather than assuming that vertical outlet could be cut back to permit running the horizontal pipe above floor level I decided to call the Vitra tech dept. They didn't provide a definitive response but suggested that frame may benefit from the longer drop provided from that longer vertical outlet. Its frustratingly all too common to hear manufactures giving ambiguous advice regarding how their products perform or should be installed.

I'm looking for some advice regarding connections soil stack. I have an ensuite and bathroom located back to back and the plan is to connect all the wastes (2xWCs, 2x showers & 2x WHBs) into a single soil stack which is located on the other side of a wall these two wet rooms share. The WCs will share a back to back concealed cistern ,the waste from this will push into 90 degree bend then a 1 metre horizontal run through the wall and then connect to the soil stack with a 90 branch. My question is if there is a preferred method of connecting the shower and WHB wastes to the soil stack. A neat option could be to combine the 2x shower waste connections to the stack along with the WC connection with this triple socket 90 branch. Or is it better to use strap bosses or even these McAlpine bosses and make individual connection to the stack? Also are there rules concerning shower/WHB wastes connect to a soil stack above/below WC connection to the stack?

Thanks John very helpful. Plan is not to have a hot return, therefore in very simple terms for now this would look schematically like: 22mm or 15mm pipe from the cylinder to a 6 port manifold located in the cellar adjacent to the cylinder, or possibly in the utility room above Then from that 6 port manifold 6x single 15mm pipes to: Bathroom Ensuite 1 Ensuite 2 WC Kitchen Utility Then within each bathroom/ensuite a 2 or 3 port manifold feeding shower/basin/bath as necessary.