Hello everyone - new to the site and planning a new build in Northern Ireland

[Muellar]

I'm looking at doing a self-build in Northern Ireland, hillside overlooking Lough Neagh and we have planning permission approved for a 1.5 storey (as part of it will be basement to make the most of the slope and eaves height restriction). It will be about 280m2 in area. To make it minimal impact we decided to go with a dark metal/zinc cladding on the main front/side and we would have a simiple render on the rear as this will be east/north orientation.

 

Due to the location and exposure I was going towards ICCF and the woodcrete blocks - I've read the various pros/cons and love/hate with Durisol which still baffles me. The more I read the more I feel that even Isotex has issues as well. I may end up just going with one of these EPS blocks, but I liked the idea of a more natural product onto which I could render and have some breathability. The search goes on.....

 

As for energy and heating my current view is to have UFH, a wood burning stove in the main living/open plan area with a heat exchanger to get some input to a hot water cylinder/thermal store. I am also considering PV both on the roof and nearby as we have a large plot and maybe even throw in a Ridgeblade to make the most of the likely winds we will get. I'm not sure if I'll be able to get a heat pump in, be either gound or air sourced, due to the draw and notice by electricity provider that it's unlikely they'll support the draw, so I am considering having a tanked gas system if I need it and supplementary boiler.

 

Whilst we have planning permission we are now moving to detailed working drawings. We need to dig and lay foundations in August 2025 so there is a bit of time, but not loads. Hence I joined this forum as I'd read some contributions and felt that it woudl be good to learn more and also where possible provide some input and lessons learnt along the way to others.

[Iceverge]

Welcome welcome. 

 

Sounds a nice project. You could post your (deidentified) plans if you like. I know I should have. Plenty of knowledge that would have helped make our build better.  ICF is attractive for lots of reasons ( e.g. inherent airtightness, good thermal bridging) but equally not so for others (expensive, requires specialist tools and skills, questionable ability of synthetic renders durability in very wet climates).

 

Is there any particular reason you want to use it? 

 

If you can get your heating load to a passive level (10W/m2) or 2.8kW overall then a tiny heat pump would do you. It'd overcome the issues with the electricity supply. Unless you have free timber from a nearby source, don't mind the labour of handling it and the air pollution (both inside and outside the house) doesn't bother you I would ditch the wood burner.

 

 

 

[Conor]

Welcome. We finished our ICF house in Co. Down March 2022. 315m², passive levels insulation, 4.5pkW of solar PV, 9kW ASHP. Super cosy house. Electric for the year was £1200. Definitely don't miss a fire /burner in the slightest.

 

ICF, good build method, tho not many builders here doing it, just the three or four. Don't see any advantage of woodcrete tbh.

 

For the love of god don't put in bottled gas. ASHP is the way to go, and you'll have no bother with NIE as highly likely the one you put in will only have a max load of ~4kW. 

Edited November 14, 2023 by Conor

[Alan Ambrose]

Congrats, and you'll find the people here very skilled and very helpful.

 

A shot of the view please, just to make us jealous you understand?

[Muellar]

@Iceverge Thank you for the welcome. A friend built with ICF and I liked the feel. The site is fairly exposed on a hillside, so I wanted somehting solid and the more I looked at options the more I felt that ICF was a viable and good option. Then I say the woodcrete blocks and they appealed to me. I'd even looked at the clay building blocks and liked them over SIPS, purely for the mass and solid nature of the build. I've always believed that cavity wall has had it's day and we need to have more mass on the inside, so ICF appealed.

 

Wood supply is not an issue and we do like a modern wood fire, however whilst it's a 'nice to have' we will assess it's viability. There are a number of things we'll have to take into account and whilst it suits where we live now it may not in the future.

 

Would I just post the plans as a separate posting or as a new topic here? Sorry, maybe a dim question but I'll claim newbie learning as my excuse 🙂 lol

[Muellar]

@Conor ahhh, County Down, was very tempted to find a site there but North Coast and family drew me to Antrim area and then a site with a view that ticked a number of boxes became available.

 

Woodcrete was attractive to me as the idea of making somehting more natural appealed (used wood, cement, lime... ok, not 100% natural but aside from building a mud house with fallen dead wood I ran out of options) and the blocks have a nice weight but easy to handle and reduced the risk of blow-out. Also they looked to be more viable for rendering onto without special additives, then being able to fix into anywhere and/or chase also appealed.

 

Yes, that was an issue a friend of mine had who's an architect... who would build as there's not many ICF builders around. I've done a few projects over the years and build an extension as well as PM'd some small house builds, so I thought that if there was something I could do then I would.

 

Clearly the gas is an issue, and maybe NIE will come through, but for now they are 'No way' so I need to explore options. I'd come to the conclusion (purely on my own) that I will need some sort of backup for heating, and that meant oil/gas/wood.... preference is gas/wood gasification, and as the Mrs wants a wok burner then I veered towards gas feeling that it would have to be there in any case. So many bad stories of wood chip and pellets that I discounted that option.

[Muellar]

22 hours ago, Alan Ambrose said:

Congrats, and you'll find the people here very skilled and very helpful.

 

A shot of the view please, just to make us jealous you understand?

@Alan Ambrose it certainly looks that way, there's also some healthy debate as well which I liked.

 

I've uploaded a couple of images now I've found the 'quote' functionality.... cropped as there were people to the left but the view does go around. For context the water in the image is Lough Neagh and you can just about make out the hills in the distrance - can't decide if they are actually the Mournes or not but I'm told on a clear day you can make them out. I spent a lot of time in this part of the county and always dreamed of having a view like this so when the site became available I moved fast.

[Alan Ambrose]

Wow, that's nice :). Yeah, I could retire there...

[Iceverge]

1 hour ago, Muellar said:

and maybe NIE will come through, but for now they are 'No way' so I need to explore options. I'd come to the conclusion (purely on my own) that I will need some sort of backup for heating, and that meant oil/gas/wood.... preference is gas/wood gasification, and as the Mrs wants a wok burner then I veered towards gas feeling that it would have to be there in any case.

 

 

What can NIE give you in raw numbers? They'll be doing their sums on a 280m2 house using 40kw of heating demand and three phase heat pump. If you build properly you'll be less that 10% of that and a small 5kw heat pump will be fine. 

 

Have you cooked on induction? I've lived with all. Solid fuel, gas, ceramic hobs and my preference would be induction every time. So clean and fast. Nothing like ceramic hobs of old. 

 

Before you commit to woodcrete keep an eye on the U values. They may need lots of additional insulation to meet a good standard. 

[Muellar]

49 minutes ago, Iceverge said:

What can NIE give you in raw numbers? They'll be doing their sums on a 280m2 house using 40kw of heating demand and three phase heat pump. If you build properly you'll be less that 10% of that and a small 5kw heat pump will be fine. 

 

Have you cooked on induction? I've lived with all. Solid fuel, gas, ceramic hobs and my preference would be induction every time. So clean and fast. Nothing like ceramic hobs of old. 

 

Before you commit to woodcrete keep an eye on the U values. They may need lots of additional insulation to meet a good standard. 

 

NIE haven't given a thing, it was early stage enquiry so I can see how @Conor advice is the way to go. I'll need to get calcs done etc then go to NIE and have a sensible discussion I guess with some figures to hand to help.

 

Funny you should mention induction, a friend has gone that way and I'll pop over to see it. At present we have a Neff hob with a wok burner and I use it all the time.... old habits eh.

 

Thanks for the point re U values. I was wondering about just how insulated they are and cold bridging with the larger ribs from inside to outside but was told 'that's not an issue with the way the thermal dynamics work'. So essentially I need to set some time aside and see what I can work out, possibly with my architect who is new to ICF but keen to understand it as he believes it will become used more frequently than it is now.

[Conor]

Don't worry about NIE, if they can give you an 80amp or 100amp connection then ASHP won't be an issue. Tell em naffin. When I did our connection card the max theoretical load was only 48amp... And that includes a 7kW car charger.

[dpmiller]

^ wot he says.

But help us help you here- are there any pole transformers or cabling in the vicinity already? Distance? Photos?

[Muellar]

17 hours ago, dpmiller said:

^ wot he says.

But help us help you here- are there any pole transformers or cabling in the vicinity already? Distance? Photos?

 

This is very interesting and helpful thanks. It is changing my thinking in a good way as if a HP is viable then we could go all electric.

 

Yes, there is a pole transformer that NIE have said will need upgraded, I estimate that it's about 250 metres from from where it would eventually terminate. Unfortunately I can't find the original documents that I asked for when we were looking at whether the site was viable in terms of getting utilities to it and the cost of these. I made initial enquiries just over a year ago and then concentrated on the site legals/planning as there were a number of issues to overcome that could have killed the whole project, so they took priority.

 

In case it helps we will be 120 metres away from 2x 5 bed detached houses and about 200 m from a farm. One of the houses has a Tesla and a charge point.

[JohnMo]

On 14/11/2023 at 11:51, Muellar said:

I'm not sure if I'll be able to get a heat pump in, be either gound or air sourced, due to the draw and notice by electricity provider that it's unlikely they'll support the draw

Not sure why that would be the case. Even at 280m2, with a decent state of insulation and air tightness, your heating loads aren't going to over the requirements a 6kW heat pump. We have a 192m2 Durisol house, a long thin single storey all vaulted ceilings house (the worst configuration for low energy) our current total house draw from the grid is 2.1kW with the a 6kW heat pump running, MVHR , treatment plant and it's -2 outside. Our DHW heated during the night at -3 outside and total house draw during that period was a little over 3kW.

 

A kettle will pull 3kW from the grid, we have a panel heater that can pull 2.5kW also, but it gets used in a garden room (long story)

[saveasteading]

Is timber frame not such a 'thing' in NI as it is in Scotland?

 

I'm pleased with how ours went, using stick-build and would absolutely do the same again.

 

There now follows a strong opinion.

 

I must get along to a self build exhibition and maybe see why so many people go for ICF and the like.

As a designer/ contractor I tried hard to give eps blocks a chance but couldn't make it 'stand up' commercially. The parameters  may change for self build / beginners.

In the construction industry there has never been any excitement about ICF. The suppliers (other than a few eps, for a while) did not even target the industry.

 

Stick build also reduces exposure to large deposits.

And there is more wood down at the BM whenever you need it.

A major advantage of wood frame also seems to be the ease of cladding, both internally and externally.

Any shape or size.

 

I cannot find any  open costing comparisons, but stick build must be 20% cheaper, maybe 40% cheaper, and less risky, than ICF.

 

I'd actually love to be proved wrong, ie that ICF is a great and affordable thing.

 

 

 

[Muellar]

13 hours ago, JohnMo said:

Not sure why that would be the case. Even at 280m2, with a decent state of insulation and air tightness, your heating loads aren't going to over the requirements a 6kW heat pump. We have a 192m2 Durisol house, a long thin single storey all vaulted ceilings house (the worst configuration for low energy) our current total house draw from the grid is 2.1kW with the a 6kW heat pump running, MVHR , treatment plant and it's -2 outside. Our DHW heated during the night at -3 outside and total house draw during that period was a little over 3kW.

 

A kettle will pull 3kW from the grid, we have a panel heater that can pull 2.5kW also, but it gets used in a garden room (long story)

 

Thanks @JohnMo it was a conclusion an ill informed me had come too after picking up initial hesitation of NIE and also reading up about power issues generally where ASHP was mentioned. But I also recognise that we need to have some decent calcs on it all and that is now the next path - take the outline design and work it up more thoroughly so we know what losses/loads we'd have so we can decide. But feedback from you and others is making ASHP look more viable - thank you and all.

 

Sounds like we may have a similar design at least in part as we'll have valuted ceilings - at least in the living/kitchen/dining area. Most post of those plans I have....

[Muellar]

8 hours ago, saveasteading said:

Is timber frame not such a 'thing' in NI as it is in Scotland?

 

I'm pleased with how ours went, using stick-build and would absolutely do the same again.

 

There now follows a strong opinion.

 

I must get along to a self build exhibition and maybe see why so many people go for ICF and the like.

As a designer/ contractor I tried hard to give eps blocks a chance but couldn't make it 'stand up' commercially. The parameters  may change for self build / beginners.

In the construction industry there has never been any excitement about ICF. The suppliers (other than a few eps, for a while) did not even target the industry.

 

Stick build also reduces exposure to large deposits.

And there is more wood down at the BM whenever you need it.

A major advantage of wood frame also seems to be the ease of cladding, both internally and externally.

Any shape or size.

 

I cannot find any  open costing comparisons, but stick build must be 20% cheaper, maybe 40% cheaper, and less risky, than ICF.

 

I'd actually love to be proved wrong, ie that ICF is a great and affordable thing.

 

 

 

 

I've never been a timber frame person, grew up in a home of builders and played with blocks as a kid and then along came timber frame, all the damp issues, rot etc... I know things have come a long way but I like that mass/heavy build.

 

Now I know NI isn't Florida so we don't get hurricanes, but to get the view we'll have well we aren't in a sheltered location in a valley basin... we'll get whatever the Westerly throws at us and you only have to look at the orientation of the main runway at BFS airport to see what way those prevailing winds come. Oh, and that's pretty much our entire front orientation. And it'll be windy (noise) so I'm factoring that into my thinking here too.

 

It wasn't my reason for ICF, I helped a friend out who built with it back in 2017 and the finished units he and his wife have built are really nice to be in, quiet and just darned comfortable and solid. They ticked all the boxes for me.

 

And like you i'd love to see some real stats on ICF v Timber frame v SIP v Clay v Block/brick cavity...

 

Controversial; do you think that owner builders take a longer term view than a builder/developer who wants to flip and move on so see the value in ICF beyond that initial build cost? I only say that as I've had this in office builds as the client where i wish the developer had just spent a bit more and made my ongoing costs and functionality better for me as the occupier/user. We're looking to build and live in our home for as long as we can, so our 'payback' horizon is say 8+ years.

[saveasteading]

3 hours ago, Muellar said:

Controversial; do you think that owner builders take a longer term view than a builder/developer who wants to flip and move on

Maybe some do. Maybe most.

But most small to medium size contractors are proud of their reputation, don't want hassles and don't want bad publicity. 

As a design and build contractor, we weren't into housing but chose timber kit frame for nursing homes, clsd in brick / render / timber,  which leep the damp out. . No problems.  In fact, by the timd the vapour barrier goes on, it won't get wet again.

But for big spaces it wasn't the right way.