Self-build in Perth & Kinross - hello

[Iceverge]

On 21/09/2023 at 08:19, Kelvin said:

Interesting how things work out.  The in built book case at the top of the stairs wasn’t supposed to be there. That whole void ought to have been a cupboard. However due to the various construction problems HH caused us we had to re-route the MVHR ductwork up through here plus there’s some extra steelwork above that doorway. The option was to just create a void with possibly an access panel on the bedroom wall. However I decided to box it in and use some of the void to create that inset book case. It will come half way up with space for a nice picture we have above it. The beam was also never supposed to be exposed but this was the beam that caused us a bit of trouble so we decided to leave it open as a reninder 😂 While it’s not a big bit of solid oak the glulams are actually quite nice in themselves. I’ll oil it etc to bring it out a bit. Had we not had these construction problems to deal with we might well have not done any of this. 
 

The other issue HH caused us is the first floor height is wrong so the ceiling downstairs above the kitchen is much lower than it should have been by 120mm! I managed to reduce that by 35mm by reducing the floor insulation from 210mm to 185mm and cutting the 45mm wall plate out, adding back in a 10mm cement board and lowering all the full height windows. What a palaver that was. It does mean we’ve still gained all that extra height upstairs so the bedroom ceiling height is 2.6m and exposed beam room 2.9m. It also means the ceiling heights in different parts of the house are all different which I keep telling everyone is characterful. 😂 

 

Always look on the bright side!

 

On the plasterboard, was it standard 12.5mm slabs and skim or are you doing special?

[Kelvin]

It’s all 15mm plasterboard plus skim and one strip of 9mm on the steel beam that spans the kitchen to make it fit flush with the 15mm on the kitchen ceiling. Another balls up by HH builders we had to correct. 

Edited September 23, 2023 by Kelvin

[Kelvin]

The other job I started is boarding out the garage in 12mm shuttering ply and painting it. I got the ply really cheap (£7/sheet) and 40 litres of matt emulsion for £16 from TP. 

 

 

[Kelvin]

Boarding the garage finished. Unfortunately the plasterers got held up on another job so have promised to start over the weekend. Also did a big tidy up so the site is looking neat and tidy again inside and out. I also got the differently tinted glazing unit replaced in guest bedroom so now all the windows match again. Unfortunately they managed to badly scratch the alu cladding. It’s being replaced next week. In hindsight I’m less convinced the alu cladding is a good idea. It might be replaceable but most of mine is behind the timber cladding so it would be quite a task to replace it. Fortunately the bit they damaged is at the bottom so accessible. 

 

I was chatting to someone yesterday who was asking me about some of the advantages of building your own house. Apart from all the obvious things I told her the thing that’s surprised me the most is how quiet it is. The other day, when the wind was gusting above 45mph here, you could barely hear it. It was quite surreal to watch the trees bending under the force of the wind but for there to be little audible evidence of it. Also there no rain noise on either the flat roof or the metal roof. Compare that to the metal garage and thing sounds like it’s going to take off. That said, it’s surprisingly airtight with very few drafts. 
 

Big week next week. I finally get the borehole plant equipment installed and all the drainage and PTP installed. 

[saveasteading]

1 minute ago, Kelvin said:

less convinced the alu cladding is a good idea 

 

Who suggested  ali in the first place? Is it promoted at self build shows?

[Kelvin]

Was all on us. We went to look at the windows and preferred the slightly cleaner alu clad look, longer warranty, theoretically lower maintenance than timber painted. They are so easily scratched though. I’ve got several bits spare that were delivered damaged (dented or bent) so have experimented to see how robust they are to scratches and not very is my conclusion. The Lindab rainwater goods are also easy to scratch. Ours are anthracite and I reckon the galvanised steel might have been less easy to scratch the scratches won’t show. 
 

It’s all fine now but not sure how well it will age. 

[Dunc]

Sounds like great progress! 

 

17 hours ago, Kelvin said:

... did a big tidy up so the site is looking neat and tidy again inside and out....

 

Surely this deserves a couple of photos then 

[Kelvin]

5 minutes ago, Dunc said:

Sounds like great progress! 

 

 

Surely this deserves a couple of photos then 

😂 ok. 

[bgmill]

@Kelvin Overall, how would you rate the Lindab gear? Besides the ease of scratches, would you recommend it?

 

We currently have this specced for our build, also in anthracite to match windows

[Kelvin]

It’s really nice stuff. Very straightforward to install. Not too dear. 

[saveasteading]

46 minutes ago, bgmill said:

how would you rate the Lindab gear

I've used it a few times, including currently on the Highland project,  and rate it highly.

[Kelvin]

It’s the little things. When we were setting everything out, which feels like a lifetime ago, we mulled over whether to set the garage and house perfectly in line or set the garage back. The debate was it either has to be bang on or the garage purposely set back enough so that it looks intentional as if it was marginally out it would long wrong. It took a bit of mocking up both structures to get it right. It’s spot on which always makes me smile because it’s only me (and the groundwork guy) that cared about it as we stood there in the rain and cold with a line and some timber. 
 

 

[Kelvin]

Probably the most important part of the build has started, the borehole plant install. Well maybe other than finding water in the first place. Our recharge rate isn’t fast hence the biggish tank.  Water was borderline whether we needed a water softener but decided to include it, and the water test showed there to be nitrite present which they’d never seen before. They think that after use this might disappear but we’ve put the treatment in anyway. 

 

One complication that wasn’t made clear to me was splitting the incoming water into softened and raw (for drinking)  isn’t so straightforward due to how the water needs to be routed. The raw water needs to bypass the water softener but still go through the rest of the filtration and the UV and not come from the pumped tank. The pressure vessel holds 30 litres and is at the front of the plumbing so we can take a tee from here and route it through the filtration and to the house with no pump (it’s about 3bar from the pressure vessel) but it means fitting another UV light either here in the garage or under the sink. Something worth thinking about if anyone else ever comes across this problem and indeed this post! 
 

 

[Kelvin]

I thought I’d do a longer write up about my water supply as it wasn’t that straightforward to get where we are now, a plentiful supply of potable water, and I’ve learnt a few things along the way. 

 

As we all know, no water no house so it’s an important part of the self-builders due diligence when buying the plot. While there is mains water nearby our plot it’s insufficient for the existing few houses. The few houses get their water via various sources, mains, boreholes, a well, and out of the burn. 
I made it a condition of the sale of the plot that the farmer had to find a water supply on the land which, in our case,  was going to be via a borehole.
 

There are lots of people out there that can drill holes in the ground but the lesson here was definitely if you buy cheap you buy twice as the first guy the farmer used failed to find water and made a right mess of the neighbouring house. I recommended he use the same company that drilled the other boreholes in the area which he did and they eventually found water at 147m. Most boreholes are mapped by the British Geological Survey and generally a scan of the drilling report is attached to the map location. This isn’t going to tell you if you’ll find water on your plot of course but it is useful to know. 
 

https://mapapps2.bgs.ac.uk/geoindex/home.html?layer=BGSBoreholes&_ga=2.140231729.386343147.1696503272-1218241145.1696503272

When a borehole is drilled you need to make sure you also get the drilling report and the water analysis. This will confirm if the supply is viable as it will tell you the yield and what treatment may be necessary, if any. This is important to know as the difference in cost can be many thousands of pounds and might dictate how and where you put all the necessary equipment. For example, if the yield is significant and no treatment is required then you need minimal equipment therefore less space and cost. Typically the drilling company will pump the borehole for a while. In our case this was two weeks. It’s worth noting that drilling a hole in the ground is a messy process. There’s a lot of material comes out of the hole. If they don’t damp the drill with water this sandy material will go everywhere. In our case it covered the neighbour’s house in red sandstone dust. Not a great start with our only neighbour. 
 

Our drilling report showed there was enough water for 60 people assuming a daily water use per person of 150 litres/day. Our borehole yield is 380 litres per hour. It sounds a lot but it isn’t in reality and one company I spoke with described it as technically dry. They look for at least 500 litres/hr as a minimum. The water analysis showed that it was moderately hard and borderline for a water softener. It also showed very slightly elevated nitrite levels in the water. Nitrites can be treated in the same way as nitrates and removed via reverse osmosis or ion exchange. Two companies I spoke with reckoned the nitrite levels would probably reduce over time such that no treatment would be necessary. After a bit of research I decided to install both the water softener and the nitrite treatment filter anyway. However, I wanted to have non-softened drinking water in the house as well as the softened water. This complicates the plumbing of it all slightly which I’ll talk through later. 

The borehole comes up to a wellhead and into a headworks chamber. For very simple installs, that requires no treatment or intermediary storage tanks, the chamber could be a large kiosk that houses all of the equipment for your water supply to your house. These kiosks are quite large and stand 1.2m tall typically. That’s not an issue if you are able to site it all at your boundary or at the bottom of the garden hidden out of view. If your install isn’t as straightforward then you might need a separate shed or space to house all the equipment in. In this case the headworks chamber just makes safe the borehole and associated control electronics for the borehole pump. It might also include a heating element.
 

I found it quite hard to get specific information on how to build the headworks chamber. All of the companies I spoke with said this is to be supplied by others. The only thing they stipulated was it had to have at least 300mm of space above the borehole and ideally 400mm of space around it. They can be above ground or below ground but if below ground you need to make sure that excessive ground water can’t contaminate your water supply. A friend has a poorly installed borehole chamber that floods when there’s heavy rain and contaminates his water with groundwater. 

 

SEPA handily provide a guide on best practice for building your headworks chamber which I mostly followed. 
 

http://www.groundwateruk.org/downloads/SEPA_borehole_construction.pdf

 

I also considered using concrete well rings with a secure cover but this became expensive and logistically hard to achieve given the weight of them but worth considering if you have the space and means to do it. 
 

I spent an inordinate amount of time deciding on the chamber dimensions. It needed to be big enough for ease of access without being too big that it dominated that part of the garden. To some extent this was determined by the manhole cover dimensions. I decided on 750mm x 750mm and ordered a Clark Drains cover from the drainage superstore. I built the headworks chamber out of concrete blocks as I already had the materials on-site with a dimension of 800mm x 800mm. 

This turned out to be a poor decision for a few reasons. It seems 750mm square manhole covers aren’t that common so the choice was limited. They are also really heavy so aren’t very accessible if they aren’t at ground level which mine isn’t. The Clark Drains cover I bought was poorly made as the frame is very flimsy and the lid quite heavy which only fitted if I hammered it into place. Concreting the frame in place didn’t work  as the concrete fell apart as soon as I tried to remove the lid. Ideally I really wanted a plastic lid for ease of access but they don’t seem to exist other than specialist lids that cost a fortune. I then happened across this company: 

https://www.forecourtsolutionsltd.com

 

They make bespoke plastic covers among other things. I sketched out what I wanted and they turned that into a workable metal frame and plastic cover. I’m really happy with the final chamber. The lid is watertight and easy to access. I have included a drain at the bottom protected with rodent mesh at either end. The electrics and MDPE water pipe enter through a sealed hole. I’ll backfill around it to reduce the height of it a bit and eventually plant around it to hide it. I’ve included the electrics for a heater but haven’t installed a heater yet. I’ll insulate it for this winter and see how it goes. 
 

The borehole is 147m deep with the pump at 80m. It has water level sensors at 10m then every 20m. It’s designed to pump the water from 50m to 80m then stop to let the borehole recharge. This is controlled by a control unit in the garage. 
 

Our borehole recharges quite slowly, too slowly to use the water directly without an intermediary tank. The picture below shows the layout. From right to left we have a 30 litre pressure vessel which takes the incoming borehole water. This goes through a 50 micron filter, then into the water softener. From here it goes through the nitrite reduction treatment then into the 1000 litre storage tank. It comes out of this tank into the Dab Esybox mini 3 (which is very quiet) then into the 5 micron filter and finally through the UV disinfectant system. From here it then goes out to the house. In addition there's an outlet to an outside stand pipe. We also have ‘raw’ water outlet to the house for a single drinking water tap. It goes through the 50 micron filter and the nitrite treatment then into the house. I’ll have to add another 5 micron filter and another small UV disinfectant system in the plant room in the house. It’s also not pumped so will just rely on the pressure vessel to get it to the house. 
 

 

The total cost for the plant equipment, installation, and commissioning including a type B water analysis and 4 bags of salt was £9909 ex VAT. The borehole cost was separate and very expensive (£18,000)  but I didn’t pay for that. 

I looked at a number of companies to supply and install the equipment as follows: 

 

Highwater - they drilled my borehole and did a neighbour’s install. I found them difficult to get a quote from and when I did it was extortionate at £18,000 not including the nitrite treatment and estimated £24,000 including it. They are known to be expensive. 
 

Rayburn - couldn’t get them to return my calls

 

GRC - spoke to them a couple of times but didn’t get a quote from them

 

The Water Man - really helpful, estimate was around £8000 but he’s a one man band and extremely busy so decided not to use him. He has a good reputation though. 
 

Filpumps - The company that I went with. I attended a webinar on private water supplies hosted by The Scottish Self Build team which Filpumps presented. I’ve found them great to deal with throughout. Very flexible and quick to respond. The installation guys were great, neat, tidy, and helpful. 
 

A long post but hopefully of some use to anyone that might need to install private water supply. 

[ToughButterCup]

A really interesting read. Reminds me of the trials and tribulations that @Jeremy Harris had.  I used to think that a private water supply would be a wonderful thing to have - not now

[Kelvin]

I read that whole saga. It had me worried about ours! Like Jeremy I was a bit concerned about power use. I started working it out but stopped. Ultimately it is what it is. 

[saveasteading]

Interesting, and agreat service to future readers.

What size of storage tank? We installed 3m3, just in case the dribble from our distant spring reduces or freezes. In the worst scenario this is a useful enough quantity to import by bowser.

[Kelvin]

It’s a 1000 litre tank. 1m3 isn’t huge especially if you had to import water in case there’s a problem as it’s about 3 days supply for 2 people. I contemplated going bigger but decided it will be fine. The only two issues are freezing in the winter at the borehole head but I will be able to mitigate that or the supply has a problem. If that happens I’ll have bigger worries to solve. 

Edited October 6, 2023 by Kelvin

[Kelvin]

One final thing I forgot to include. I mentioned the first failed borehole. It’s 137m deep and only a few meters from the live borehole. You may ask why didn’t the second drill company use that hole and go deeper. Why indeed! But it wasn’t my money. 
 

However I am left with a deep hole. Best practice is backfilling with similar material that came out of it. The drilling report breaks this down. Alternatively backfill with bentonite granules for dry filling. At the moment I’ve fitted the cap from the other borehole to seal it but it is something I need to sort out eventually. 

[Thorfun]

how wide is the borehole? is it possible for someone to fall down it or is it pretty narrow?

[Kelvin]

Oh no chance of that. 10cm diameter. 

[Kelvin]

Never rains but it pours. 
 

The rain over the last 48 hours has been awful here. Flooding everywhere. My site has stayed very dry though so all good. Then I noticed this morning someone has cut a track in the verge into my plot which diverted all the rainwater from the road into the field which has run down the boundary to my electricity kiosk and washed out some of the ground around it. I don’t believe it was done out of spite just not thinking although why direct water onto someone’s land of course. Spent all day shoring everything back up. 

[saveasteading]

32 minutes ago, Kelvin said:

why direct water onto someone’s land 

It's a standard thing to shift water off roads, usually into a ditch.

[Kelvin]

5 minutes ago, saveasteading said:

It's a standard thing to shift water off roads, usually into a ditch.

Not off the road into what effectively is someone’s garden. There’s a ditch on the opposite side of the road. Fortunately the ground runs away from my borehole here otherwise it would have flooded into the headworks chamber then down towards my garage. 

[saveasteading]

Where I live, these outlets have a terminology ( not offlet, but that sort of thing)  which I can't remember, and are shown formally on drainage maps. Probably to avoid what has happened to you.  I'd probably get my shovel out and move the outlet across  the road. Check where it will  flow first.