epsilonGreedy

I got a 2.5% weekly overrun rate on my scaffolding. With the threat of regular sites closing you could try for a much better overrun deal.

My index finger under the downhill end of my long spirit level gives a fairly consistent 1 in 80 gradient. A tip given to me by my nearly retired building advisor.

Things should move swiftly from dig to pour for conventional strip foundations, so I think it unlikely a pandemic crunch point will arrive during those few days. You could consider opting for a maximum trench fill with fewer footing block courses, this is a relatively cheap trade off between cost and advancing your build quickly. Once the first course of footing/trench blocks is in you can relax and no longer worry about 6" of water pooling on top of your concrete fill.

How good is your site insurance? I am thinking personal accident should someone fall in.

Do you know the square meter size of your home? Also what energy performance score did the property get on completion?

In the present situation that concerns you, the best and simplest security system is a local community you can depend on.

Ah ha I had not considered that a room air draw stove would fight with the MVHR.

Ok good to hear this is an option otherwise a fireplace on a solid floor slab would form a large cold bridge.

I just consulted the Building Services Handbook, defo very bad form to take a long route through the house foundations, cavities and voids. @joe90's builder did the right thing going around the house outside, then into the internal point of delivery via the shortest path.

Is it standard practice not to run floor insulation under the hearth? We have allowed for a 2" to 3" thick hearth plus say 65mm of floor flow screed across the whole room, even so I do not want to worry about insulation sheets below the fireplace melting.

Yup all part of the plan. The sitting room wood burner will draw air horizontally through the cavity wall because there is a subwall mid way down the room that bisects the fireplace where the stove will sit hence through the floor is not viable. Clearview manufacture custom air ducts for their stoves to be supplied externally. The Snug stove is more problematic because the fireplace backs up to the rear hallway. I hope when I scrape back the builders crud on the floor I will find that the beam spacing permits me to core drill a 75mm hole down into the suspended floor void which will provide a fresh air supply. I thought the smaller 5kw stove could draw air from the room without an air brick but apparently that is not allowed in a new build.

Given some of the strong views on his subject expressed here I have at times wondered if I should just plonk 3 false chimneys on the completed house. However earlier this week we drove nearly 4 hours across country to visit a specialist stove showroom and when sitting in the kitchen exhibition room while one of the staff sketched out a design I could hear the background sound of the stove drawing air and was convinced again I want a working wood burner. In practice I doubt it will be lit more than 30 days year.

Yes an RM78. I just looked at the product spec 78Kg... no wonder I struggled to carry that across the site. I must admit getting the design of the chimney right is taxing me and my lead brickie. I have already demolished the first 2m high chimney breast because it intruded too far into the room, my error. A timely technical chat with Clearview Stoves clarified that fitting our favourite stove design with its 14kw output was absolutely nuts. Apparently the quoted variable ranges of wood burning stoves should not be relied on, they achieve their optimum cleanest burn at maximum rated output. Now we are designing for a smaller stove and ClearView confirmed the external air draw kit does not require additional fireplace depth, we have been able to knock 200mm off the chimney breast depth. After viewing the many working stove displays at ClearView's fabulous showroom in Ludlow we also discovered that a wood burning stove looks quite attractive when set 50mm forward of the chimney breast face, so that is another 50mm clipped off the chimney breast. The main design challenge we have is that my external chimneys, which stand 1.9m proud of the hipped roof, have an old fashioned wide look. We have to settle on the external chimney dimensions now because it simplifies the chimney build if the flue base dimensions continue straight up through the roof line. I have dry built a small demo chimney in facing bricks and 5 bricks by 3 seems about right.

Oh too late, I had previously phoned my now regular BM and they quoted for their standard 175mm off the shelf flue parts. I actually have two working chimneys to build and have enough flue sections onsite to build one. I could revise my plans and fit a larger 8" flue in the larger fireplace if there is a good reason to do so? The smaller fireplace is being built to accommodate a 5kw wood burner stove with a 6" flue outlet. The other fireplace will have a larger 8kw stove ( yes I know far too much for a new build, it is an aesthetic choice for the room size) and according to the Clearview brochure this also has a 6" outlet. Your post prompted me to review chimney flue sizing and this following site suggests matching chimney flue size to stove flue size or the chimney flue can step up a bit in size but not too much. The same site also goes on to say the fireplace opening should be x10 to x12 the flue size though I do not anticipate ever operating an open fireplace. https://www.mychimney.com/blog/chimney-fireplace-sizing/

I found this installation diagram on the ClearView web site which suggested a 12 to 1 mix. Not sure what Leca is, a brand name for vermiculite? https://www.clearviewstoves.com/useruploads/downloads/Pg10. 07 drawing Pumice Liners.pdf