Pete

[ICF_needing_brick_cladding]

Hi Folks, hope you're all well. I've recently received full planning permission to build a new three storey end of terrace house in the side garden of my existing house in Leeds. There's a decent amount of space so the new house will be about 50% larger (about 200m2) than the existing 3/4 bedroom house. It will be just 6 metres from a 40mph road though. I'm thinking of using ICF because it's a MMC and it's quite airtight etc but mainly because it's good with external noise. Obviously I'll need half decent windows too (please sing out if anyone has fitted windows in a house near a fairly busy with good acoustic results). My main concern with ICF is the expense and warranty fuss of brick slips (the front and rear elevations must be clad in brick to match the existing houses - totally understand that but sadly they are the ugliest bricks man has ever conceived and I'll likely have to spend a fortune making the new house look ugly too). Can anyone recommend an ICF system that works particularly well with brick slips and and particular brands of brick slips. I contacted the LABC warranty folks. At first glance, they don't think the Elastolith acrylic brick slips that I'd seen will be acceptable and generally favour a brick slip system with a cavity behind it - not good news as that'll increase the wall thickness and fuss. Anyway, any advice would be much appreciated. I love the idea of building the house in ICF but the cladding issues are really putting me off and I may have to revert to brick and block.

 

Also wondering whether to go for brick and block on the ground floor and metal web joists on first and second floors to make fitting the MVHR easier. Any other suggestions? In a related issue, also unsure whether to go for underfloor heating on the ground floor only or all three floors.

 

Currently trying to tweak the design with some fairly minor non-material amendments.

 

I'm still going (thanks if you've made it this far) - I also have to have a phase 2 physical Coal Mining Risk Assessment and a physical Contaminated Land Survey (about £6k/granite worktops). It's in a high risk area for coal mining (as apparently 15% of the UK is) and there were three small Victorian terraced houses on the plot previously that were demolished to make way for the new, ugly, 1975 terrace here today. Any advice on that front would also be appreciated.

 

Many thanks,

 

Pete

20004 A-23B Site Plan As Proposed 17-Dec.pdf 20004 A-25B Elevations As Proposed Sheet 1 of 2 16-Dec.pdf 20004 A-24B Plans As Proposed 16-Dec.pdf

[ProDave]

Hi and welcome.

 

My only suggestion is why do you want to join it to the other houses?  Given the plot you have I would now be re submitting planning to make the new house detached from the rest of the row. Even if that makes your new build slightly smaller.

[FM2015]

Some will probably shoot me down on this but I'd say most EPS ICFs will work with products from https://www.matclad.co.uk/product-category/brick-slips/

They are not ugly! And can make slips from your choice of bricks.  Not sure what that costs though.

[PeterW]

Cut slips come in at around 50p each plus the cost of the bricks and they sometimes don’t get two from each so they can get quite expensive. Plenty of manufacturers out there but when you add the cost of backing systems or grid system and adhesive and grout / pointing they can be quite an expensive solution. 

[ICF_needing_brick_cladding]

Thanks everyone for your replies. The planners steered me towards another end of terrace - the pre-app was for a detached house. Also, if it was detached it'd need to be stone clad given the other houses at right angles to the terrace. 

[Russell griffiths]

Are you going to live in it or is it for selling. 

 

The reason I ask is there a market for a big house like that. 

[Ferdinand]

I would also carefully consider that garden wall as an acoustic barrier.

 

There is a lot that can be achieved looking eg at systems used for barriers between estates and dual carriageways, plus you have a little elevation to play with.

[ICF_needing_brick_cladding]

Thanks folks. @Russell griffithsthat's a fair question. The house is for me to live in and I could happily live there forever. However, I probably would sell eventually. The response to my plans from local estate agents has been very positive. I appreciate they're unlikely to get much business otherwise. It's a popular area and the views are good from the gable end. 

[Brickie]

Have you considered brick effect render? 
Not something I’d normally endorse but given you may be stuck with an expensive system giving a finish you’re not even happy with,it’s worth looking into. 
Some houses had it near where I used to live (retrofitted) & it was only the EWI & detailing at openings that gave it away,and even then,only when staring at it whilst stuck in traffic.  On a new build that could be eliminated with a bit of thought at design stage,I’d guess

[Ferdinand]

A further idea is brick-effect painting.

 

Or as panels.

[Iceverge]

Welcome Welcome. 

 

Congrats on having gotten this far. 

On 06/02/2021 at 21:33, ProDave said:

 

My only suggestion is why do you want to join it to the other houses?  Given the plot you have I would now be re submitting planning to make the new house detached from the rest of the row. Even if that makes your new build slightly smaller.

 

I had a nose on google maps and if you could get permission for a detached house to the style of those on the main road It'd be easier to build and probably be worth much more given the extra kerb appeal. I went through 3 planning permissions before we settled on a house. I'm glad we did as we'd have run out of money otherwise. 

 

If this isn't an option I'd look at squaring out the ground and first floor and binning the internal garage. Make the house a full 10250*7440 box.  A simple external car port will prove more useful in day to day use and I'd increase the size of the utility, make a proper plant room and make the kitchen larger. 

 

For noise I'd bin the bifold doors and get triple glazed doors with proper compression seals. 

 

For a construction method, if you're stuck with external brick, I'd use  wide cavity walls like @tonyshouse. As i remember the only noise issues he had were through the ceiling and would recommend double boarding them. I'd also probably use a dense insulation like cellulose, rockwool or woodfiber. 

 

In preference I'd move all the bedrooms to the North of the house as this is where you'll be most noise sensitive.  

 

On 06/02/2021 at 20:41, ICF_needing_brick_cladding said:

metal web joists on first and second floors to make fitting the MVHR easier

A top plan. Combine this with a vertical service shaft from a plant room and you're onto a winner.  

[Bitpipe]

I think any decent triple glazing solution will deal with road noise - if you're already considering MVHR and are planning to be airtight then you won't have trickle vents or other penetrations that would enable additional noise transmission.

 

I'd say about 50% of our glazing is non openable anyway, mostly the feature windows (slots and column styles).

 

Regarding UFH, if you're approaching passive standards of insulation and tightness then you may be ok with GF only  - you should really model it first in a tool before you make a decision.

 

What is your slab strategy?

 

Think also on overheating, solar gain etc.

[Nick Laslett]

What is the issue with standard bricks and ICF?

 

I’m only familiar with the system I’m using, there are no cladding restrictions from what I can see. Thermohouse manual 2018 page 68

https://thermohouse.co.uk/wp-content/uploads/2018/07/Technical-Manual-2018.pdf

 

I looked at the LABC Certificate and there is nothing there about cladding restrictions. LABC EWW178 Thermohouse
 

https://thermohouse.co.uk/technical-spec/

Drawing detail for Standard brick and Stone cladding

 

 

Edited February 13, 2021 by Nick Laslett

[Nick Laslett]

I’ve done no research on brick slips, but next page of technical manual doesn’t list any restrictions. Most ICF apartment blocks seem to be brick slips, more economical than standard bricks?
 

 

[ICF_needing_brick_cladding]

On 13/02/2021 at 10:59, Brickie said:

Have you considered brick effect render? 
Not something I’d normally endorse but given you may be stuck with an expensive system giving a finish you’re not even happy with,it’s worth looking into. 
Some houses had it near where I used to live (retrofitted) & it was only the EWI & detailing at openings that gave it away,and even then,only when staring at it whilst stuck in traffic.  On a new build that could be eliminated with a bit of thought at design stage,I’d guess

Thanks for your reply. I have actually. Sent a link or two off to a Warranty company to approve earlier this week. The response (from the Build Zone related company) was that as long as it's ok with Building Control then all is well. The bricks I need to match are an unusual and fairly light colour - they look cheap and nasty. I'll have to investigate further whether it's possible to get close enough to a match with BER. I need to provide the planning dept. with a 1m2 board with the chosen solution so they can approve it.

[ICF_needing_brick_cladding]

On 13/02/2021 at 12:07, Iceverge said:

Welcome Welcome. 

 

Congrats on having gotten this far. 

 

I had a nose on google maps and if you could get permission for a detached house to the style of those on the main road It'd be easier to build and probably be worth much more given the extra kerb appeal. I went through 3 planning permissions before we settled on a house. I'm glad we did as we'd have run out of money otherwise. 

 

If this isn't an option I'd look at squaring out the ground and first floor and binning the internal garage. Make the house a full 10250*7440 box.  A simple external car port will prove more useful in day to day use and I'd increase the size of the utility, make a proper plant room and make the kitchen larger. 

 

For noise I'd bin the bifold doors and get triple glazed doors with proper compression seals. 

 

For a construction method, if you're stuck with external brick, I'd use  wide cavity walls like @tonyshouse. As i remember the only noise issues he had were through the ceiling and would recommend double boarding them. I'd also probably use a dense insulation like cellulose, rockwool or woodfiber. 

 

In preference I'd move all the bedrooms to the North of the house as this is where you'll be most noise sensitive.  

 

A top plan. Combine this with a vertical service shaft from a plant room and you're onto a winner.  

Thanks for your reply and suggestions @Iceverge. I'll take a look at Tonyshouse. I can only have obscure glazed windows on the east side of the building so I'm not overlooking neighbours. Cheers

[ICF_needing_brick_cladding]

On 13/02/2021 at 12:40, Bitpipe said:

I think any decent triple glazing solution will deal with road noise - if you're already considering MVHR and are planning to be airtight then you won't have trickle vents or other penetrations that would enable additional noise transmission.

 

I'd say about 50% of our glazing is non openable anyway, mostly the feature windows (slots and column styles).

 

Regarding UFH, if you're approaching passive standards of insulation and tightness then you may be ok with GF only  - you should really model it first in a tool before you make a decision.

 

What is your slab strategy?

 

Think also on overheating, solar gain etc.

Thanks for your reply @Bitpipe. I didn't realise there were modeling tools for such things - I'll investigate. Overheating wise, I'm thinking of having the top floor landing full height and having a velux to let the hot air escape. Same in the top floor lounge. I'd also hope the MVHR could help to cool the house in summer but not sure how effective this would be.

 

No slab strategy yet. Was thinking beam and block due to the slope.

 

Thanks again

[ICF_needing_brick_cladding]

On 13/02/2021 at 16:58, Nick Laslett said:

I’ve done no research on brick slips, but next page of technical manual doesn’t list any restrictions. Most ICF apartment blocks seem to be brick slips, more economical than standard bricks?
 

 

Thanks for your reply Nick. Real bricks would add a fair bit of thickness to the house and as the gable with of the house is only 7.5m it's something I'd like to avoid. I do think that could be cheaper than brick slips though, as bonkers as it sounds. Cheers

[Iceverge]

1 hour ago, ICF_needing_brick_cladding said:

Thanks for your reply @Bitpipe. I didn't realise there were modeling tools for such things - I'll investigate. Overheating wise, I'm thinking of having the top floor landing full height and having a velux to let the hot air escape. Same in the top floor lounge. I'd also hope the MVHR could help to cool the house in summer but not sure how effective this would be.

 

No slab strategy yet. Was thinking beam and block due to the slope.

 

Thanks again

MVHR won't heat or cool your house as the air transfer is too low. 

 

Regarding overheating there's a simple formula somewhere relating to glazing vs floor area. I'll try to find it.  Stack ventilation via your velux will work but you're better off not having the issue in the first place. 

 

Don't discount cavity walls. With 150mm full fill dritherm 32 or EPS beads you could achieve the same U value as your ICF. Less issues with finding specialist materials and experienced trades. 

[Bitpipe]

11 hours ago, Iceverge said:

MVHR won't heat or cool your house as the air transfer is too low. 

 

Regarding overheating there's a simple formula somewhere relating to glazing vs floor area. I'll try to find it.  Stack ventilation via your velux will work but you're better off not having the issue in the first place. 

 

You will need do a SAP analysis by default but a PHPP analysis is a few hundred pounds if you're interested in approaching that standard.

 

SAP will give you some indication and PHPP will give you a more accurate model. There is also a 'home grown' heat loss model floating around this forum that can help you estimate the space heating requirement.

 

If your footprint / glazing area is now fixed (i.e. you have planning) then you only need to the hard work of defining the house once and then you can play with different wall and window U values.

 

+1 to the MVHR - its needed to effectively ventilate an airtight structure without incurring heat loss but it's not effective at significantly heating or cooling. Consider making provision for a split air con (if you have PV, this effectively runs for free in summer).

 

We have stack ventilation (Velux Integra in atrium) - works well to cool house in the evening during summer and then you can lock in the cool air for the following day. Keep in mind that in an airtight house, the stack needs a way for the air to get in at ground level so consider designing in an openable window that can provide this without creating a security issue.

 

We didn't really consider it at design / build time but have found that opening a GF slider a few inches and locking shut is effective. Best would have been to have an openable window in our basement.

[Iceverge]

On 14/02/2021 at 21:36, Iceverge said:

MVHR won't heat or cool your house as the air transfer is too low. 

 

Regarding overheating there's a simple formula somewhere relating to glazing vs floor area. I'll try to find it.  Stack ventilation via your velux will work but you're better off not having the issue in the first place. 

 

Don't discount cavity walls. With 150mm full fill dritherm 32 or EPS beads you could achieve the same U value as your ICF. Less issues with finding specialist materials and experienced trades. 

Hi @ICF_needing_brick_cladding

 

As per my previous post a quote from. There's good info about shading there too. 

 

https://elrondburrell.com/blog/passivhaus-overheating-design/

 

The UK’s Passivhaus Trust recommends aiming for windows in a south-facing wall to be a maximum of 25% of the external wall area. This should be adequate for daylighting except in the case of very deep rooms. Windows in other walls should be considerably less than 25% of the relevant external wall area and designed around views, daylight, ventilation, and aesthetics, as per the previous point.

The UK’s Passivhaus Trust also offers as a rule of thumb that glazing (excluding frames) should be around 15 – 20% of the Treated Floor Area of a Passivhaus building, as a starting point.

Aim for rooflights to be 10% or less than the room floor area.

[ICF_needing_brick_cladding]

Thanks again @Iceverge and @Bitpipe, I'm really grateful for your knowledge sharing and suggestions. I'll spend some time considering your replies and the related info/concepts. Apologies for the delay, I've been sidetracked with spending £6k on surveys (CMRA boreholes and contaminated land assessments)! The CMRA went well, fingers crossed the CLA on 18/06 does too. Either way, I hope you're thoroughly enjoying the start of summer!

 

It's been suggested to me that I could couple the ICF walls (I can't seem to shake off the desire to build with ICF) with a SIPS roof. Any thoughts on this would be appreciated. Perhaps I ought to begin a new post on the subject. I'm even wondering whether I should willfully make the overheating issue far worse by having a wider windows on the top floor (maybe even a glazed gable as the full height lounge is almost asking for it) to exploit the view. Then maybe sliding doors with the two in the middle moving outwards and obviously a barrier. I'm getting carried away really but worth considering all options at this stage.