Self-build in Perth & Kinross - hello

[Kelvin]

Hi all,

 

I've just realised I started a thread before saying hello here so hello ?

 

We have had an offer accepted on a nice plot near Blairgowrie that has planning in principle. I am just going through my due diligence at the moment before parting with any money. The plot won't be the easiest plot to build on as it's on a slope, drainage will be private, the electricity supply estimate is higher than we expected, and the water supply will be via a borehole although the land owner is going to cover the cost of drilling the hole. 

 

We are currently looking at two options in terms of build, one is using a local architect who has a good reputation and the other is a slightly customised Heb Homes Longhouse. 

 

Very early days

[Becca]

We are near you... about 8 miles from Blair.  Just waiting on our building warrant and hope to start on our site in September.  Our plot is also on a slope and with a high FFL, so I had to abandon an insulated raft foundation and we're doing a TETRiS beam and block.  Glad to say we don't have your complications in terms of drainage, leccy and water, though our house stretches from one side of the plot to the other, so access to the back for big machines isn't going to be possible.

 

Good luck with yours.  Look forward to reading your posts.

[Kelvin]

Our plot is between Blairgowrie and Alyth. 

 

I was reading about the TETRis beam and block system the other day. I really liked it as a solution. 

 

Be good to keep in touch since we'll be neighbours lol. We're about 9 months behind you I think though. How has P&K planning been to deal with? Also be good to hear who you've used from  a trades perspective. 

 

Good luck for September. Exciting stuff. 

[saveasteading]

Welcome. 

 

I wouldn't worry about the private drainage as long as you have plenty of land. Easy and not too expensive as long as it is thought through.

It is potentially much cheaper to install a digester tank than dig under a road for a connection.

Then no sewage bills.

 

Is the ground good for drainage?

 

Electric supply...there isn't much you can do about the cost if they have to upgrade the supply. A new transformer on an existing post is a common requirement and £10k for starters.

 

Beam and block is pretty fool proof and especially if access isn't great.  I would assume that Tetris or other polystyrene equivalent has got to be (?) better than concrete blocks then insulation. But maybe expensive, I don't know.

 

[Gus Potter]

On 29/07/2021 at 12:21, Kelvin said:

Hi all,

 

I've just realised I started a thread before saying hello here so hello ?

 

We have had an offer accepted on a nice plot near Blairgowrie that has planning in principle. I am just going through my due diligence at the moment before parting with any money. The plot won't be the easiest plot to build on as it's on a slope, drainage will be private, the electricity supply estimate is higher than we expected, and the water supply will be via a borehole although the land owner is going to cover the cost of drilling the hole. 

 

We are currently looking at two options in terms of build, one is using a local architect who has a good reputation and the other is a slightly customised Heb Homes Longhouse. 

 

Very early days

Yes welcome Kelvin.

 

Sloping sites offer up many opportunities.. but how much of a slope do you have?

 

In terms of your foul water treatment given that you are on a slope a soakway may not work unless you have a very big plot. But if you are up in Blair you may have that really free draining soil..good raspberry/ strawberry ground. Worth a look at this as it varies quite a lot.. in which case a soakaway might just work. You may need to go down the packaged treatment plant route.. then often you can discharge to a water course. A lot of folk think about a bio disc, lots of moving parts but now you have aerated ones that are pretty cute.

 

I've speced one from the folk in the link below.. it's still to be installed and commisioned though! There are other suppliers so have a browse round the subject as it's your sevices that can cause a cost / design risk issue.

 

https://www.wte-ltd.co.uk/sewage_treatment_options.html

 

They have an air blower that sits above the ground and no moving parts. Also, you can get ones that cope with low flow conditions.. ideal for holiday homes..if you don't feed the bacteria regularly they die off, just like house plants.

 

What you could do is to gather together all the info you have on the site you want to buy and turn it into a single document if you can. Then find an SE who will spend a bit of time reviewing what you have, doing a bit of research.. say half a day..call this a preliminary desk top study. Then meet them on site and pick their brains. Say half a day for this. Add in a bit of travelling say hour each way.. just call it two days 16 hours. Now for good experienced advice and provided you are flexible this excercise may cost you £1500.00 plus the vat not always as some SE's keep below the vat threshold.

 

Sounds a lot but although that is the headline rate the SE will probably spend more time than you realise, then also answer any emails you may send asking for a few extra tips and extra advice. If you put the fee into context and compare this with what you Solicitor is charging then it's not bad. Currently a good trades person costs easily grand a week.. the SE only needs to give you one or two good tips particular to your site and you will easily cover their fee.

 

The idea is that they impart enough information to you which will give you sufficient knowledge to make an informed decision as to for example, whether you go the Architect route or the Heb homes way.. do you proceed with the purchase or not. They should also give you loads of extra tips in the half day on site about the ins and outs of say the local builders and a whole load of other stuff, materials and so on. You can cover a lot of ground in that half day on site so even if you don't buy this site you'll know a lot more for the next time.

 

Hope it all goes well and enjoy your journey.

 

 

 

 

[saveasteading]

I am currently going for a different manufacturer, based on good experience, ease of installation and cost.

Open for other options though.

 

Good idea to talk it through with an SE, (as described here, although this is Civil, not Structural, Engineering. Good design will save you more than the fee. Possibly much more if the design is (apparently) effortlessly good from the start.

[SuperJohnG]

Welcome. 

 

Do your homework on services costs and you'll be fine. 

 

Sloping site will add major costs but not unmanageable but as mentioned can add interest which I like. 

 

My power connection was 18k (3 fields, 6 poles and 400m) but was easily executed as landowners were happy for me to pass through so check where power incoming from and ensure you can get it there and agree with landowners if passing through.  

 

Borehole. That's good owner will pay for drilling however doesn't guarantee water so caveat that. I would have it drilled prior to purchase if mains isn't available.  Trust me on this one...from a man who cried when we done a 120m borehole which was nearly dry and the a 60m hole that was even drier...it was 15k and I properly man cried about it. Then the budgeted price supplied by the borehole company, for the pump and treatment, went from 4k to oh we can do it for 8k. So get the drilling done and include in missives, then allow 10k for the supply and treatment.  Then you'll be OK. 

Edited August 4, 2021 by SuperJohnG

[Kelvin]

I'm in the process of organising the ground investigation so will have a better idea of what we're dealing with then. 

 

The significant electricity cost seemed to come from their suggestion than the transformer needs reinforcement, without this the cost would be much lower. I have asked for a review of that which I'll get in the 11/8. One of the poles is within the boundary on plot. You can see the cable on the survey data below. 

 

The vendor is organising the borehole company now. I'm expecting the drilling report and chemical analysis. 

 

Here's an extract of the topo survey. The whole plot is 1.1 acres. The house will be in the north eastern sector.

 

 

 

Edited August 5, 2021 by Kelvin

[Kelvin]

I thought I’d update my introduction.
 

Hard to believe my first post was in July 2021!  Suffice to say we achieved planning and got our warrant in December. Frustrating process largely down to the timber kit company and their incompetence, inexperience and general shoddy service. That’s a whole other story. 

 

The electricity supply ended up being extremely cheap costing us only £416 plus my time to dig the trench (6m on my neighbour’s land and 20m on ours) and a small foundation for the kiosk. Far cry from the £26.5k initial estimate. 
 

The water supply was slightly more complicated but eventually the farmer managed to successfully find water. Took two different drilling companies and a very deep hole (147m). The first few treatment plant quotes were almost laughable at £24k. I then attended a webinar organised by the Scottish Self-Build team and came across Filpumps from Aberdeen and they quoted £9k so that’s who we’ve gone with. Plant gets installed in a month or so once the garage goes up. 
 

The sewage side of things proved to be pretty straightforward. Percolation test was fine and the Goldilocks spot happens to be 50m from the borehole and 10m from the water course plus. We decided to go for a Graf One2Clean 7PE system with remote blower. Great price from JD Pipes. It gets installed in a few weeks. 
 

The big challenge was trying to find a groundswork company. Emailed 7 companies and got three quotes. Two of them took months to get and were horrendous. The guy we went with was £20k cheaper! He’s also very good and has come highly recommended even from the local BCO. 
 

I’ve been working my way through all the other elements, prelims, roofing companies, plumbing, electrical, joinery, ASHP, MVHR, PV and garage supplier. I’m pretty much there with all of them. Got a decision to make on plumber and joiner. Everything else is in place. We’ve also got the kitchen designed and ordered, bathrooms picked, and flooring mostly decided. 
 

Groundswork has started. We’ve cleared the site, levelled it, formed the driveway and did the setting out today. Foundation digging starts tomorrow. We should finish the foundations by third week of March. Bit of a break for a few weeks then the kit arrives on the 17 April. Garage goes up end of March. 
 

We have a decision to make about the small but long retaining wall which we’ll do this week and we need to make the drive wider. 
 

 

Edited February 27, 2023 by Kelvin

[Gus Potter]

1 hour ago, Kelvin said:

I thought I’d update my introduction.
 

Thanks from me for the update.. great to here you are making progess.

 

My wife is up in Blair tonight seeing a pal.. small world!

 

Keep us updated!

[Kelvin]

The guys have taken full advantage of the good weather. Foundations dug, poured, and initial blockwork up. Will be finished tomorrow. Garage foundation will be dug out tomorrow and all the trenches for the ductwork. The cold weather might put the brakes on the slab pour until next week. We have a retaining wall to dig out. We don’t really need to do it as we can grade the ground but it’s not huge and we think it will look better. Plan is to build it in block then clad it to match the house. 
 

 

[Kelvin]

Another fine day here. Very cold though and it’s not going to warm up until next week so has put the kibosh on the slab pour which has meant delaying the garage build and therefore the borehole plant installation by a week. 
 

However cracked on with planning and digging out for all the ductwork and prepping the site for hardcore coming in for the perimeter. Managed to pour the garage concrete foundation before the temperature plummeted. 
 

 

 

[Kelvin]

Ducting all in. I’ve somewhat overdone it but better to have it and not need it etc We have power in to the house and back to the garage plus a spare to garage as batteries etc are all in there. Data between the garage and house primarily for Starlink which will be mounted on the garage, power and control for the ASHP, power to the treatment plant and a spare out the east elevation in case we power the gate, power out the front and back of the house, power to the island, two water pipes for softened and raw, the duo insulated pipe for the ASHP. I also installed some extra ducting coming out of the garage for charging point, outside 13A, power for the borehole pump and power to the potting shed. 
 

 

 

 

[Kelvin]

Foundation wall built. A bit of a panic this week though as the insulated blocks didn’t turn up two weeks ago, then last week and then again at the start of this week. Started to doubt they were going to turn up at all so tried to find an alternative. Managed to talk Tarmac in Cumbria into supplying me as a cash sale but I had to arrange the haulage. Another afternoon on the phone and found a haulier willing to go and get them. However panic over as they turned on Tuesday and the brickies laid them yesterday and I spent the evening covering them up to protect against the frost. We shuttered the garage, laid out the garage floor insulation and DPM ready for slab pour. 
 

On Monday I’m meeting the timber kit company on-site to check the foundation and measure for the steels. We’ll then pour the slab for the house. 
 

I’ve decided to go ahead with retaining wall rather than grade the slope. I also think it will be a nice feature once I’ve clad it to match the house. 

[Kelvin]

Fun and games with all the rain slowing us down a little so have got hardcore down all around to make site easier to work on. 
 

Meeting with timber kit company was interesting. The purpose of the meeting was to check the foundation ahead of the kit manufacture and delivery next month plus access, and delivery details. We had to talk them in to actually measuring it because it ‘looked fine’ We’ve already measured and it matches the drawings (2mm out in one dimension and 3mm out in the other, no diagonal on the drawing but it’s all square) but I wanted the kit manufacturer to satisfy themselves it was fine otherwise why bother coming out. It’s also in their contract. Eventually they did it. 
 

This week we’re finishing off preparations for the slab pour on Friday for house. We’ve delayed the garage slab pour until next week.  Drainage is all in and capped off. I said not to put the inspection chambers and manhole covers in place until after the kit is up in case they ran over them in the telehandler so we’ve banged some posts in for now. 
 

I now have all the trades lined up to hit the ground running as soon as the kit is up. The plan being to go as fast as we can so that we’re more or less complete by October. 

[saveasteading]

17 minutes ago, Kelvin said:

in case they ran over them

Because they would run over them. Very practical. 

 

As previous discussions, I hope you used a metal measuring tape with quality approval. 

 

[Kelvin]

Yes we had a discussion about that too. We used their measuring tape which was indeed metal. The kit has a 10mm tolerance  (not sure what the regs say 20mm?) 

 

The kit erection company were grateful we’d not fitted the manhole covers etc. Generally people don’t think to leave them out at this stage and they do get damaged as you say. The groundswork company need to come back and install the PTP plant later anyway so all that can be done then and when the scaffolding is down. 

 

We also had a debate about the cold spots at the internal door thresholds between the two sections of the house. In the end we built the wall continuously, they’ll fit the kit and I’ll cut the blocks out under the doors. 
 

Edited March 22, 2023 by Kelvin

[saveasteading]

Nice work. 10mm to big and it will easily stretch. 10mm short and the kit will hang over. 20mm sounds very rough.

 

I would now paint the exposed blockwork with bitumen paint. Just the blackjack stuff and a big single use brush. One coat into the joints and another all over. It keeps out damp and deters moss etc,  but also looks tidier, as in nobody will notice it.

 

I don't understand the issue with internal door thresholds.

[Kelvin]

The house is in two parts. The main house and a long ‘porch’ (what HH call it) that has three door openings. The foundation blockwork runs continuously under these door thresholds so, as it currently is, I can’t run the insulation continuously under the doors nor the screed or UFH. The groundswork company are more used to leaving the blockwork out for the doors. However HH wouldn’t sign this off as they couldn’t be confident the kit would match the gaps in the blockwork perfectly. I questioned this because there’s a big steel upright right at the door into the lounge and we have a pin in the well we’ve formed to centre this. Hence why we’ll need to cut the blocks out beneath the door openings once the kit is up. 
 

 

 

[saveasteading]

Ok, sounds like the right solution.

 

I understand HH caution. Not every  job will be as professional as yours.

A few times in business our clients did the foundations, and it was always a problem in some way. Either we had to work with it or wait for their people to sort it (unhappliy).  Dimensions, levels, quality, unfinished. 

 

This way it also keeps the superstructure solid and level during construction,  then when you knock out the blocks it will arch over and not deflect. 

 

Everything is for the best....etc

 

[Kelvin]

I couldn't be happier with the groundswork team. We've worked really well together and they're are doing a top job. I'd easily recommend them in the Perthshire area which is mostly where they cover. 

[Kelvin]

Regards painting the exposed blockwork. The construction details note that the exposed blockwork should be rendered over the metal lathe. I'm getting a quote for this. Painting it in blackjack would be a much cheaper option as I'd just do that myself when the weather improves a bit. 

[saveasteading]

I had a standard detail for blackjack on block. ( hundreds of projects). The normal  options were to  leave it alone, which looks poor, or use facing brickwork. Nobody ever questioned it, and it lasts indefinitely. 

Not so confident with render on lath in contact with the ground.  Is it an upmarket finish for the sake of it?

Assuming that there will be 150mm or so exposed below the wall cladding.

[Kelvin]

1 hour ago, saveasteading said:

Ok, sounds like the right solution.

 

I understand HH caution. Not every  job will be as professional as yours.

A few times in business our clients did the foundations, and it was always a problem in some way. Either we had to work with it or wait for their people to sort it (unhappliy).  Dimensions, levels, quality, unfinished. 

 

This way it also keeps the superstructure solid and level during construction,  then when you knock out the blocks it will arch over and not deflect. 

 

Everything is for the best....etc

 

Yes I understand it too. 
 

Our groundswork guy generally works with the same architect and SE and it seems they’ve worked out the best way to ensure accuracy from the beginning. He normally fixes the steelwork verticals ahead of the kit coming as it makes his life a bit easier but HH prefer to do this as part of the kit erection. 
 

The brickies that did our block foundation said that a fair proportion of their work is fixing other people’s poor work. 

[Kelvin]

4 minutes ago, saveasteading said:

I had a standard detail for blackjack on block. ( hundreds of projects). The normal  options were to  leave it alone, which looks poor, or use facing brickwork. Nobody ever questioned it, and it lasts indefinitely. 

Not so confident with render on lath in contact with the ground.  Is it an upmarket finish for the sake of it?

Assuming that there will be 150mm or so exposed below the wall cladding.

Yes 150mm. When I think about it one of the HH show houses I looked at the blocks were left alone and the other one they were painted black. I’m sure I took a picture of them too so you’ve jogged my memory!