mvincentd

How were you planning to finish externally after the cill if you were not going to trim the eps down anyway? ie; what was going to conceal the top of the eps given it appears to be only a few mm lower than the cill? I'm wrestling with a similar complication.

....doesnt a disabled bathroom door have to open outwards (to mitigate someone slumped inside blocking its opening inward)?

Generally also be aware that when co's say they can do any RAL colour it's rarely true because there's numerous RAL ranges and many suppliers don't even seem to realise they are actually only offering from say the RAL CLASSIC range....which is nothing like ALL of the RAL colours.

There's another one (or maybe the same on?) just off Lulworth Avenue right on the corner of the Hamworthy Park carpark, i'm 99% sure is a durisol build, I saw blocks going up in October.

Nice...looks sturdy!

I dunno, but check that with supplier. Mine were all specifically marked to show 'top chord' and it wasn't optional to flip them.

That's me, four times so far. ...twice just last week but thats only because i managed to resist the inclination the other 14 times.

Jeez, thank ek for that, i'm having a crisis of confidence about all aspects of my build currently and that question had me in a right panic...

Surely 250mm of waterproof concrete with a fully bonded 0.8mm thick waterproof membrane is going to be more airtight than parged thermalites(or indeed most materials any house is constructed with)?. All external walls are either poured concrete or they're thermalites/135mm full-fill dritherm/flintblocks.

Replying quickly so not sure if i'm off the mark but this is word for word what i put to my Building inspector and he approved it; Hopefully a quick question, i’ve been phoning but never seem to catch you right. Most northerly wall is the garage and the top sits roughly 1 to 2 feet below a 6ft fence on boundary with next doors garden (no nearby structure)….and less than a metre away from it. The fascia is planned to be cedar untreated. Likewise the garage east and west walls would have cedar fascia which would at their most northerly point get within a metre of that boundary fence. My understanding is that the cedar, battening etc should be fire treated. Is this stuff sufficient to meet the requirement?; http://www.fireproofspray.co.uk/flametect-c-wd-for-wood-clear-flame-retardant-68-p.asp meets BS476 class 0 & 1. This stuff means I can fascia the rest of the house and not have it look different to the bits in this fire sensitive area as this spray doesn’t alter the visual appearance of the timber.

I have a good friend with a business supplying and fitting Sofar (he's a bit more commercial than domestic orientated). I've just checked with him if he could do a special deal for build hub on a pooled order for several systems. I told him you've already identified sub£2000+vat for 4.8kw, supply only. He said by all means collate a total order requirement and he'll better that, but it will be fairly marginal as thats already a very tight price. If this is of any interest let me know.

ah, thanks for that...hadn't thought about air tight but not vapour tight......i'm now wondering if parge coat falls into that category, otherwise i've precious little of my outer box thats breathable! (monolithic structure of waterproof concrete throughout floor and 2 sides whose waterproof membrane is continuously bonded to the roof membrane, then above the blockwork wall's joist plate i've xps thats about to be air taped to the roof deck and joists).

...point below presumably? 1st- I'm pleased to have been able to be of some help....but please don't mistake me for someone in any way qualified to make engineering judgements....at the end of the day I was just chewing the fat with you and all. Cullens said you could block the top and bottom sections but that it was not necessary....so i took from that my assumption of not critical at an engineering level. However I thought surely good practice to replicate the original intended 'shape' of the joist as far as possible given those parts surely provide some enhancement to performance (for one example don't the hangers have holes for twist nails going into those areas and aren't ALL holes supposed to be nailed). I only drew in the bottom yellow block out of laziness but yes it would make sense to do this at top too, but i'd think the bottom is the most important bit to remediate, and this is why; Remember that unlike your earlier joists these were designed not to be top hung, so here the bottom chord is the primary bearing point onto the hanger and without the addition of the bottom yellow block the 'too short' bottom chord is only catching maybe half of the hanger base. I know the hanger base isn't the be all and end all because of the twist nails through the sides....but my instinct has me more comfortable utilising all the hanger base, just as @joe90's design does.

Appreciated Mike, sorry the main thrust of my question was intended to be "under my current scheme are the contents of my ceiling void gonna be ok?" rather than am i going about airtighting my outer box the best way.

Apart from road edge to gateline, ie the visibility splay area, usually 4.5m I think....I cant imagine why they are trying to dictate tarmac all over your drive and personally i'd look to have the condition removed. In the interests of storm water management surely they shouldn't be unnecessarily promoting the use of non permeable surfacing. chuck some gravel down.

I really don't understand why they are saying the filler block (particularly at bottom) isn't necessary, given its so easy to achieve and surely good practice at least even if not critical at an engineering level. Their drawing shows a single block reaching from back of joist hanger to joist vertical. Might they baulk at splitting that into two blocks...suggesting a shear line is introduced as per pink on drawing below left. In which case does drawing right mitigate.

ah, that explains why its possible to buy a pre hung fire door set that doesn't include one.

To act as a fire door it has to be closed! The only door in our house we ever close is the front door. I wouldn't go putting them where they aren't 'required' therefore.....and where they are required that requirement extends to them needing to have an auto-closer.

A current thread on air tight tests and the comments it's generated has got me thinking.... I am due to dot and dab plasterboard, and this 'layer' would constitute my airtight layer. All my mvhr in/outlets would serve the air within the house compartments bounded by this airtight layer. I have a warm flat roof, so if prior to dot and dab I also make the 'shell' airtight (as recommended) by using blower proof on the internal block walls, air tape on all the wall/roof junctions, etc......I will end up with an inner airtight box inside an outer airtight box. One of those airtight boxes will be above ceiling and below roof deck, will contain joists, mvhr ducting, services etc.......but will not have any mvhr actively serving that area. Is this fine and correct or should I be looking to achieve a not-brilliant level of airtightness in the outer box? I know i'm not living in the outer box, creating moist air etc.....so guess this is the key point.....but suddenly it feels a bit odd so thought i'd check opinion.

I countersunk wherever I encountered the clash. If you just faff a bit to get your first joist (or set of hangers) parallel to the wall it runs alongside then just cut a 400mm spacer to hold against the fixed hanger(joist) and mark for the next one.....your ostensibly oblong room is going to have to be very 'jelly' to throw the joists significantly off parallel. Give consideration to your decking sheet size and plasterboard sheet size...your first joist is likely 50mm off the parallel wall face, you might not want your 2nd joist at 400 centre because continuing that way will put the 4th joist centre at 1200+50+(0.5xJoistwidth) yet you're only going to set your plasterboard maybe 10mm off the parallel wall face. Defo strong backs and mvhr ducting slid in as you go.

for my flat green roof posijoist co' states the following; top chord live 1.5 kn/m2 top chord dead 1.42 bottom chord dead 0.25 They were asked to design them by my SE who would have given them his calcs as below;

Sorry to hear the outcome, but good that they have this suggestion for remediating the existing joists rather than entirely new ones. Like others, I too think @joe90 has a better design...to the point that i'd bet this is what they really mean but have drawn badly. Its a wholly unqualified opinion but i reckon their drawn idea won't work, but Joe's will. Good luck.

I believe minimum joist bearing is 90mm...so typical allowance 100mm in line with typical width of a block wall. I'm concerned that theres a possible misinterpretation here (worth approx 100mm) that you carry into this 2nd joist order when you; ...is 3646 the physically measurable distance of durisol to durisol, or is it (for want of a better way of putting it) 'being expressed as such for simplicity having taken into account a couple of things'?

Damn...i've written at length then lost it all. To cut a long story short; There's a pre production drawing detailing a 3546 joist including ends constructed such that they can withstand 50mm trimming either side should it in some cases be necessary. I'd guess they required you to sign this drawing off before production, particularly as I believe they didn't do the on-site measure? So regardless of all other facts they are in the clear if the joists now actually measure 3546. In any case 3546 seems correct to me given you supplied a 3646 measurement for wall to wall........you have 2 x 50mm wall plates and a designed hanging system requiring both top and bottom chord to fit between them, ie in a space of 3546. Just go measure and find where the deviation (and liability) lies.

sorry missed this while typing my essay!