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It isn't a door, it is a single fixed pane window about 1.5m wide and 2.4m high. Yes I used foam at the sides, you can see some yellowed and waiting to be cut back flush at the edge in the photos. I agree it seems best to have something capable of supporting the window from underneath. Would the EBT set hard as it seems to say it is flexible ? And wondering if it has any insulative value ? The aluminium frame has a thermal break in it, so if I could avoid creating a thermal bridge underneath across the outside frame and the inside frame it might help keep the bottom frame a bit warmer internally. Maybe push in some XPS at the back and then EBT or something at the front ? Or maybe I could try cutting some slivers of celcon block ?

A pump mix is designed according to the local materials. Eg river gravel flows more readily than crushed rock. Then the stone and sand are mixed to a recipe provided by their lab. There is an additive too, basically a detergent. The water content is prescribed too and they even allow for how wet the sand is. That's naughty re theadded water. I've known operatives to sign thinking it was a delivery ticket, not about water. Maybe the driver thought he was being helpful, not understanding the issue. But they should be trained to know. It's a mass footing so should be ok. Adding water for any complex structure or for a slab is not acceptable, so instruct all your people and each delivery driver on arrival next time. Re the quantity. I've never known an issue so the likeliest reason is your estimate... sorry.

Thanks guys. I'm going to press the MEP designer further on these points to list out exactly what functionalities we require from the BMS - to understand if this is the correct approach.

That's interesting. We never requested extra water and I've just checked the ticket and the driver checked that box. My wife who had nothing to do with the pour, signed it without thinking 😮‍💨

I just asked for C25 and as we used a pump, I assumed they'd do the mix accordingly as it was clear it was for footings. It was a volumetric supply and mixed on site, not ready mixed.

Water is only added if requested. A pump mix does not need extra water either. Unless it is a mix on site (volumetric) wagon, then you will only have what you ordered. If it is mixed on site then they will provide more until you say to stop.

It is a new rear extension. Two pipe loops into a manifold and the heat source is a gas boiler with a mixing valve of course. Floor Area about 37 sqm, ceiling height 2.6m, 90mm PIR walls, 150 PIR in warm roof and under slab. As you can see pipes were not put under the kitchen island or kitchen unit wall area - so maybe 5 or 6sqm unpiped floor area. The heating has been operational for a couple of years since we had to ditch the original builders. I have had the concrete getting up to 26C with the current settings, but it has often had some protection mats or other coverings over chunks of it. Never really tried to optimise (or calibrate the heatmiser wireless thermostat) as it has been in various unfinished state but now plastered. I have omnie TorFlor2 heating in the suspended floor in the adjoining house. Just thinking if I had a probe then the heating could be arranged to turn off if the floor temperature went above 26C say.

You pay by the load you order, if you only wanted 24m³, that's what you should have asked for. What slump did you ask for?

Just looking at the ticket and they ticked extra water added via customer request. We never requested extra water be added and I'm not sure if this is the default when you use a pump?

Bldg Regs require 0.18W/m2K for an extension. Yes, yes, yes!! Do wet plaster. If you must adhere plasterboard do it either on full-coverage adhesive (rare as rocking-horse poo) or with full perimeter bead and close cross-hatchings. Better still, don't use it!

When I looked, the window/door companies seemed to offer this as an option on their products. I'm sure vastly overpriced for what is a magnet and a reed switch (cost <50p). With planning I expect you could plan to retrofit something to windows doors just after they are installed but you would be putting holes in the frame and not sure how that affects warranties, etc. (though a common window install method holes in the frame as well so can't see it being a huge deal). Not got far enough to think about this in more detail.

I should add, on the fire/smoke issue, we do have one in the building I'm a director of the RTM (separate from the BMS I mentioned above). It's entirely seperate from everything else. Designed to be manually controlled by breakglass (though our recent FRA suggested it might need to be wired into the fire alarm now). Quick look at our budget at it looks like it's costing us about 2k a year for firealarm/smoke ventilation system maintenance, for a 6 story/27 flat block (below 18m where extra regs kick in).

Recessed magnetic contact sensor / reed switch as used in alarms - depends on your doors / windows, then just need someway to make that info available to your blinds

No. The electrician will sheath the cables as required with the appropriate colours when he connects it all up.

Doesn't sound crazy. (I'm not expert, I've been involved in precisely 1 BMS system and was mostly hands off and not impressed with the final result). The above can all be done with relays (and a timer) so don't necessarily need a computerised control. Worst case a PLC with the ladder logic printed out and stored in the cabinet so it can be replaced if it breaks. Having said that if opening windows if the fire alarm goes off is a requirement for fire safety you may well get into a much more regulated area with the need for certified systems, battery backups, regular maintenance, etc. The other points seem trivial to do. I would stay away from anything more heavily computerised if you can. You'll just be paying an endless series of extra bills. Every bit of equipment you buy will likely cost more up front and then you'll be paying specialists to configure and maintain them, etc. I'm about at my limit of useful contributions here but even if it doesn't help me say more it may help others if you could say more about what the requirements/specifications are for this building.

This was just an example of a previous job the MEP designer shared. He was saying there needs to be a control system for the ventilation, AC, Heating, openable windows, etc, e.g: - Interlock to prevent AC and heating operating at same time - Interlock to disable AC and ventilation when windows are open - Possibly some automatic opening of windows when Fire Alarm triggers etc Does that make sense ?

We got it sorted eventually and the two final trucks arrived together, but the buggers fleeced us and the driver went to my wife and she signed the ticket and we apparently used 29.5 M3, but my calculations were 24m3

Only looking at the proposed panel, I see nothing on there that necessarily requires a BMS system with complicated setup. Just hard wires into the various systems. Does he want this wired up to a BMS controller that then has interfaces with all these systems or is he just proposing a panel where you can see the status of everything at a glance. Doesn't look like there is anything complex going on, so keeping it simple with some hard wired indicators and switches and no computers involved seems like the obvious answer. (If you need a simple PLC for sequencing relays then sure but can't see why you need a full BMS which will a likely 5 digit number to your costs).

This is one of the concerns I have for the biggest room in my build (which is well over a year from completion), although I'm confident I'll be able to solve the problem with some cheap DIY acoustic tweaks (thin pads on the ceiling, soft coving, absorbent art work, etc). I can't stand trying to hold a conversation in a room with loads of reverb, & if my hi-fi is not performing as it should I get quite annoyed. A friend's new house suffered terribly from this reverb problem when she held her house warming party. It was very difficult to decipher what was being said in her 70m2 or so room with vaulted ceiling & several different conversations going on at once. By the time of the next party, there were two sofas & a big (4m wide) floor to ceiling book case full of books, & the problem was gone. I briefly considered having a slightly sloping ceiling & non-parallel walls, for the benefit of my hi-fi, but I decided this would be impractical.

Hi Going to be putting electrics into my shed 50m from the house with some solar on the shed. Electrician has told me 25mm SWA 3 core but does it matter about the cable colours brown / blue/YG or brown black grey thanks

That makes sense. Any recommendations of how we can minimise Total Cost of Ownership? I'm worried about capex, as well as license fees and maintenance fees. Also, any recommendations systems ? Thank you in advance.

Don’t worry about the inrush current, it’s hardly likely to make any difference whatsoever to a mechanical part like a switch. Use the Jeani switches. They’ve proven their quality for decades

Proper buildings don't put up with fragile smart home stuff (most homes don't). They want / need a robust system, that any one understands, can manage and repair - not calling in a tinkerer from their garage or man/woman shed. Hence stating you need a BMS (building management system).

That may be on the DC side, but then there will be a bit of induction on the 230 VAC side. Jury rig something up and test it. A capacitor, resistor and/or a diode across the lightweight AC switch may help (snubber).

hello folks, yes it was me that has talked about my EWI on here over the years. I did post a thread on the greenbuilding forum during my install which might be worth a look : https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=15355&page=1 and worth searching for "EWI" over there as has been discussed in huge depth over the years. I cant offer advice on costs as mine was nine or so years ago but it was much cheaper self installing the insulation as it was then a straight forward render job which most pros will quote on a per m2 basis. I can offer a few pointers: 1. EPS can be sourced from major insulation merchants. Go for graphite enhanced EWI grade EPS (the grey stuff). It's cut from aged EPS blocks so more dimensionally stable and has a slightly better r-value than white EPS. Kaycel was the reputable brand when I did my project, Baumit also sell their own. Lots of other places sell it, EWI store I think sells generic stuff but could probably tell you the provenance. 2. I used Baumit render and also their beads, fixings and mesh, it was all good quality stuff. The render (star contact white) is also used as the board adhesive. For the fixings ideally go for recessed ones (see my GBF post) as these are much neater and dont cold bridge the insulation. I would do both adhesive and mechanical fixings. 3. I got my specliast EWI beads such as for frameseal beads for window reveals (great, highly recommend) and starter tracks were from Wemico. If you need a starter track, go for plastic not metal as it is a nasty cold bridge. 4. I took my EWI right down below DPC to the top of footing. You dont need a DPC in EWI, I put a step detail in for aesthetics and also timing as I did the main elevations and then the below DPC bit about 4 years later. But you could have a contiunous run of insulation from the top of the footing to the eaves. if you have any questions, happy to help, DM me or I can reply here. Installing the EWI is fairly straight forward for a competent DIY'er. You won't need a course. It needs to be nice and flat and the boards need to be tight, any gaps can be filled with foam (not adhesive as this will cold bridge). You'll probably do a better job that most professionals as often the insulation gets put on with gaps and bodges in the knowledge it will all be covered in render. Not all renderers have done EWI installation but will be able render over it if you DIY install it, the basecoat/thincoat systems are the same over block work as over EWI. I used a pro to render and he was very happy with the flatness of the boards (I think he was expecting a bodge up). Also I recommend the mineralic silicate thincoat renders (not acrylic or silicone as these can looks a bt plasticky). Also I found the smaller grain size looked smarter, again the large grain size can look a bit cheap IMO. Baumit did a 1mm grain, standard is more like 2/3mm. EWI is great, it made the most incredible difference to the house.