MBC Timber frame prices

[Mr Punter]

Just now, Adrian Walker said:

What are the weaknesses of an insulted slab?

 

It can feel very hurt and sometimes become tearful when subjected to criticism and scornful remarks.

[Adrian Walker]

31 minutes ago, Mr Punter said:

 

It can feel very hurt and sometimes become tearful when subjected to criticism and scornful remarks.

??

[SBMS]

39 minutes ago, Mr Punter said:

insulted slab

 

[scottishjohn]

getting a price per sqm is menaingless unless unless you include everything .like kitchen ,bathroom ,flooring etc

your basic shell could be £1000sqm 

but then add on kitchens ,bathroom  flooring etc it could suddenly be 2k+ sqm-- all depennds on spec you choose  can only be valid if you get a turn key build having gone through all the details with the builder 

I dimissed the flooring cost at the begining as a small item  .but having got quotes for stick down vynl planks etc for my 400sqm --thats adds another 30k on it  

just a shell is nowhere close to finshed move  in cost,change skirtings from mdf to real wood ,like oak etc --add another couple of grand ,same with choice of doors or staircase  and then oof course the heating system 

it is not an easy thing to calculate until you have a fixed in stone design and spec .

just changing from pvc to alli windoows could more than double the price  of them 

and then of course outside landscaping and driveway  etc 

 alot of working out to do for you before you get to a valid total cost 

Edited May 30 by scottishjohn

[TerryE]

1 hour ago, Adrian Walker said:

What are the weaknesses of an insulated slab?

• Pretty much any builder in the UK knows how to dig a 600×1000mm (or whatever depth is used for local soil types) trench-type foundation and fill it full of concrete.  Making an insulated slab is still (in the UK) really a specialist exercise, so the crew needs to know what they are doing and have a true quality work ethic.  The actual sequencing of the build and pour is very tight so the crew need to be on the ball.  In our case, the concrete was a little wet and the weather cold.  The concrete is power-floated to finish and level to 1-2 mm across the entire base and the time window in the set where it is firm enough to walk on but still workable is quite narrow. If you don't do it during this window, then you might end up having to power plane the finished slab.  Our crew foreman stayed on site over night and started about 3 AM!  
   
• The approach doesn't fit well with some soil types, especially if there is a change in type across the pad.  Tree roots running near or under the pad are an absolute no-no.
   
• You need to have a pukka soil survey including cores across the site and this is probably around £3⁺K today. The SE uses to spec out the sub-base.

 

But we went from a hole in the ground that 100s of birds were using as a shallow lake to a finished slab complete with UFH loops fitted in just over a week.  It was amazing to watch the process. 

Edited May 30 by TerryE

[saveasteading]

59 minutes ago, Adrian Walker said:

the weaknesses of an insulated slab?

I'd hazard that the strength of a kit is certainty, especially for first timers to self build.

I'm not aware of any professional constructors using these systems.

 

extra cost v risk reduction. 

 

Structurally, I don't really get the principle of a very strong slab bearing on polystyrene on top of thick strong sub-base.

The slab would span several m of open space and would be heavy construction even for a big warehouse.

 

But I suspect that the design has developed over many years to overcome any issues encountered, regardless of the site conditions. Certainty.

 

[TerryE]

12 minutes ago, saveasteading said:

I'm not aware of any professional constructors...

 

MBC and at least a couple of other specialist passive house suppliers use warm-slab construction as standard.

 

The MBC SE knows his stuff and he has probably designed over a thousand such slabs.  BTW, it's not just any EPS; it's a special construction grade, designed for load bearing.  There is typically EPS 300 under the ring-beams and EPS 100 under the main floor pan.  It our case there were two load-bearing cross beams so the main 100mm pads only spanned some 3½m and had an extra 100mm (i.e 200mm deep) cross braises every 2m or so.

 

Have a search on YouTube: there are some really good time lapses of some MBC builds.

 

Incidentally, I mate of mine had a house in Texas in the Houston Bay on what was essentially reclaimed swamp.  This type of reinforced slab is the standard construction technique in his area.

 

Edited May 30 by TerryE

[SteamyTea]

2 hours ago, Mr Punter said:

 

It can feel very hurt and sometimes become tearful when subjected to criticism and scornful remarks.

Melts when the heat is on to.

[saveasteading]

1 hour ago, TerryE said:

specialist passive house suppliers

I worded it badly. as far as I know these are a supplier contractor, working for an end user.. not a developer or being built to sell.

 

I'm not saying anything about whether these are good or bad value because we all see it different ways, and have different skills and priorities.

I tried very hard to make eps wall shuttering work on several jobs but couldn't get it near to competing with other methods. But I can see it works for newcomers.

Never tried a kit for floors. I didn't even know it existed until I came on BH, probably because they weren't targeting my sort of business by direct contact or exhibitions.

 

It just amazes me that I could specify a 175 slab with one layer of medium grade mesh, on which to run 10 ton forklifts and racking up to 8m high, but these houses have 200mm with 4 layers.

[scottishjohn]

42 minutes ago, saveasteading said:

It just amazes me that I could specify a 175 slab with one layer of medium grade mesh, on which to run 10 ton forklifts and racking up to 8m high, but these houses have 200mm with 4 layers.

bad subsoil  can be the only reason for 4 layers of mesh 

[SBMS]

4 hours ago, scottishjohn said:

getting a price per sqm is menaingless unless unless you include everything .like kitchen ,bathroom ,flooring etc

your basic shell could be £1000sqm 

but then add on kitchens ,bathroom  flooring etc it could suddenly be 2k+ sqm-- all depennds on spec you choose  can only be valid if you get a turn key build having gone through all the details with the builder 

I dimissed the flooring cost at the begining as a small item  .but having got quotes for stick down vynl planks etc for my 400sqm --thats adds another 30k on it  

just a shell is nowhere close to finshed move  in cost,change skirtings from mdf to real wood ,like oak etc --add another couple of grand ,same with choice of doors or staircase  and then oof course the heating system 

it is not an easy thing to calculate until you have a fixed in stone design and spec .

just changing from pvc to alli windoows could more than double the price  of them 

and then of course outside landscaping and driveway  etc 

 alot of working out to do for you before you get to a valid total cost 

Was after the price per sqm for the kit/superstructure, not the finished article.

[JohnMo]

I was quoted about £700/m2 based on double glazed windows, with a large percentage of the money due 28 days prior to delivery. This was for a wind and water tight, kit of parts.

 

This excluded, all ground work, and all site assembly. But didn't go that direction on the end

[RedRhino]

Timber frame costs are front of my mind as we are about to select our supplier. Here is my thought:

 

1. Once the house is built no one can tell the specification of the build - what the U value of the walls is or how much insulation is in the floor. 
2. When you eventually sell the house the people buying it will probably know little and care less about U values, air tightness, cold bridging etc. Compared to other factors like location, view, parking; construction standards are down the list. 

If you broadly agree with the points above then my conclusion is that if you choose higher construction standards / cost then you are doing it for yourself and no one else. 

Saving money on construction costs buys an awful lot of energy when you can get 5% return on any cash saved / not spent. 

 

So for me I'm torn between 'buying the best' (e.g. MBC) and saving money and pocketing the difference. 

 

 

 

[saveasteading]

1 hour ago, RedRhino said:

I'm torn between 'buying the best' (e.g. MBC) and saving money and pocketing the difference. 

But you can build to the same standards and save on the margins and management and transport of the systems. With systems I would say the advantages are certainty and the package principle.

If you can manage, including managing the design, then you have a choice. 

Don't stint on quality either way.

[JohnMo]

2 hours ago, RedRhino said:

So for me I'm torn between 'buying the best' (e.g. MBC) and saving money and pocketing the difference. 

Buying a kit of parts with manpower to erect isn't a cheap option, I fell over at the prices. Then did something different.

 

45 minutes ago, saveasteading said:

you can build to the same standards and save on the margins and management and transport of the systems.

Or better if you want. Good insulation and airtightness does have to cost, it's all about the details.

 

2 hours ago, RedRhino said:

When you eventually sell the house the people buying it will probably know little and care less about U values, air tightness, cold bridging etc.

I have sold 10 houses over the years and every buyer has asked, what we pay for gas and electricity, they may not know or care about the details, but running costs is a factor.

 

2 hours ago, RedRhino said:

then you are doing it for yourself and no one else. 

You are building for yourself - no one else, don't fool yourself (unless your a full time builder) otherwise you would just buy a bog standard house. I have lived in new, old and very old houses, and nothing comes close to what we built. Looks better, feels better (MVHR and UFH) no drafts, great views etc.

 

Do it well, otherwise you won't see the benefits, and you will sell and move on.

 

As way of an example just looked back at our old house, its August gas bill had more kWh of gas consumption (heating was never switched off), than this house would use in Dec. This August will be standing charge only. So in today's terms and prices August alone is £75 cheaper.

 

[SteamyTea]

8 hours ago, RedRhino said:

buys an awful lot of energy

Buys a lot of climate change, intergenerational, environmental and political damage as well.

 

Earth’s atmosphere is trapping twice as much heat as it did in 1993

Earth’s energy imbalance, a key measure of global warming, has doubled in the past 20 years, raising concerns about how much heat the oceans are absorbing

By Madeleine Cuff

5 June 2024

 

 

 

More of the sun’s heat is getting trapped by Earth’s atmosphere

muratart/Shutterstock

 

Earth’s atmosphere is trapping more than twice as much excess heat now compared to 1993, making scientists increasingly concerned about the impact on the world’s oceans.

The planet’s energy imbalance is a measure of how much surplus heat there is in the climate system. It is the difference between how much energy enters Earth’s atmosphere from the sun, and how much is radiated back into space.

 

Earth has been absorbing more energy than it emits for decades, as increased concentrations of greenhouse gases in the atmosphere trap more heat from the sun.

This imbalance has increased sharply in recent years, according to estimates based on data from ocean buoys, published in the latest Indicators of Global Climate Change study. Between 1974 and 1993, Earth’s average energy imbalance was 0.42 watts per square metre (w/m²), but between 2004 and 2023 it more than doubled to 0.87 w/m².

“The Earth is out of energy balance, which is due to the greenhouse gas effect. There is less energy leaving the system,” says Karina von Schuckmann at Mercator Ocean International, a non-profit organisation based in France.

The Indicators of Global Climate Change, co-authored by von Schuckmann and more than 50 other climate scientists, is published annually to provide an update on the state of the world’s climate.

It follows the same methodologies as the Intergovernmental Panel on Climate Change and aims to act as an interim update to the IPCC’s comprehensive, but infrequent, assessments.

The most recent IPCC assessment, which was published in 2021, estimated Earth’s energy imbalance at 0.79 w/m² during the period 2006 to 2018.

The energy imbalance has been increasing since the 1970s, due to increased greenhouse gas emissions and lower air pollution, which helps bounce heat back into space. Previous studies, using satellite sensors, have concluded that Earth’s energy imbalance has doubled since 2005.

This is worrying news for the world’s oceans, which are absorbing around 90 per cent of this excess heat. The oceans have been warming at record-breaking rates every year since 2019, research shows. The oceans are “our sentinel for planetary warming”, says von Schuckmann.

The additional heat is warming ocean waters, making them less effective at capturing CO2 from the air, driving sea level rise and severely affecting marine life. Some of the changes could be permanent.

Recent studies also suggest the excess warmth is penetrating into the deep ocean, to depths of up to 2000 metres. This heat will take thousands of years to resurface, and in the meantime could affect ocean currents, oxygen levels and marine chemistry.

“Earth energy imbalance is not just some sort of esoteric quantity that scientists like to look at. It’s got real world implications,” says Norman Loeb at NASA Langley Research Center in Virginia.

 

Studies also suggest the rate of acceleration in global ocean heating has increased over the past 20 years, indicating the rate of change for Earth’s energy imbalance is also rising. This may be in part due to a diminishing albedo effect – as warmer temperatures melt snow and ice, there is less white surface on Earth to reflect the sun’s heat.

The rate of increase has jumped sharply even since the 2022 Indicators of Global Climate Change report, which estimated the energy imbalance at 0.89 w/m² for the 2010-2022 period. This year’s paper puts it at a record 0.96 w/m² over the 2011-2023 period.

2023 was a record-breaking year for air and ocean temperatures, driven primarily by climate change and a global swing to El Niño, a natural climate variation that brings warmer temperatures.

The jump in energy imbalance in 2023 is probably due to the sudden swing to El Niño, says Loeb. “Traditionally, when you have La Niña, the climate system takes up energy. And then when you have El Niño, it releases energy,” he says. “When you go from La Niña to El Niño, it packs a big punch.”

Alongside warnings about the increase in energy imbalance, the latest Indicators of Global Climate Change study also cautions that global average temperatures are rising at 0.26°C per decade, double the pre 1983 warming rate. With emissions at the current level, the world has just five years left before the 1.5°C temperature goal is broken.

 

Journal reference:

Earth System Science Data DOI: 10.5194/essd-16-2625-2024

[Kevin Dawson]

Another data point - for our basically 200m2 liveable area MBC two-storey Passive house and UHF-piped & screeded slab - with a couple of extras like a 3m roof extension over a balcony, a full OSB cover for the planned standing seam roof (from others) and their external masonry footing - comes in at almost exactly £200k of which £50k is for the window/door set, all erected/fitted and airtight to less than 0.6ACH.  Hopefully going up just before Xmas '24.

So £1k per square meter.

 

If anyone out there has a certified MBC house I'd be interested to compare notes........?

Edited August 24 by Kevin Dawson
editted to add timescale

[Mark Greenfield]

On 17/03/2024 at 09:31, nod said:

Never seem to get the M2 price for TF

 wry expensive compared to solids 

It's not expensive compared to traditional methods at all when everything is considered. Trad building can often end up costing more - try comparing a trad build with the same performance at timber frames such as MBC and you'll soon see why!

[CaptainDram]

@SBMS did you end up getting a quote or kit from MBC?

[SBMS]

22 hours ago, CaptainDram said:

@SBMS did you end up getting a quote or kit from MBC?

Hi @CaptainDram - we did, I got a quote from MBC, a local SIPS supplier and erector and a brick and block quote from a builder we have used before.

 

Like for like, to get to a shell for a 380m2 shell:

 

MBC Timberframe: 0.14 walls, 0.1 roof - £178,000

MBC Timberframe: 0.1 walls, 0.1 roof, 0.6ACH- £223,225

Brick and Block - 0.15 walls (200mm EPS beads cavity), 0.1 roof (Warmcel pumped) - £132,000

Brick and Block - 0.15 walls (200mm EPS beads cavity), 0.1 roof (Warmcel pumped), 0.6ACH - £136,000

 

Both need windows, foundations, floor insulation, face bricks, render, slates etc so those prices are pretty comparable.  The Brick and Block 0.6ACH includes £4k for aerobarrier who will similarly guarantee that air tightness level.

 

It was a bit of a no brainer really as I was erring on the side of masonry anyway as I just like 'solid'.

 

Also - you can really get in the weeds with U values.  I did a heat loss calculation and 0.15 walls is roughly £990 per annum in heating (ASHP). 0.1 walls (the passivhaus version form MBC) was roughly £930 in heat. Thats a payback of over 1453 years.  Law of diminishing returns when it comes to insulation!

 

[TerryE]

You need to be careful that you don't do an apples and oranges comparison.  MBC contractually guarantee passive class performance, so in our case (and others on this forum who have used them) all three MBC crews spent their time doing such builds, so they really understood the fine details of making it happen.  We got 0.5 ACH on first attempt without any trouble shooting of missed leaks.  Tightening some of the loose Internorm window adjustments to spec dropped this by another 30% or so.

 

@SBMS point is very valid if the contractors teams have a similar understanding and attention to build detail.   It is more difficult to avoid air leaks and bridging in a B&B build compared to the MBC twin-wall technique which avoids most of these by design.  

Edited December 2 by TerryE

[SBMS]

1 hour ago, TerryE said:

You need to be careful that you don't do an apples and oranges comparison.  MBC contractually guarantee passive class performance, so in our case (and others on this forum who have used them) all three MBC crews spent their time doing such builds, so they really understood the fine details of making it happen.  We got 0.5 ACH on first attempt without any trouble shooting of missed leaks.  Tightening some of the loose Internorm window adjustments to spec dropped this by another 30% or so.

 

@SBMS point is very valid if the contractors teams have a similar understanding and attention to build detail.   It is more difficult to avoid air leaks and bridging in a B&B build compared to the MBC twin-wall technique which avoids most of these by design.  

Agree to a certain extent @TerryE but a 90k price differential? That’s a lot of spare money to spend on airtightness detailing.

[Iceverge]

22 hours ago, SBMS said:

Agree to a certain extent @TerryE but a 90k price differential? That’s a lot of spare money to spend on airtightness detailing.

 

Exactly the same logic I reckoned with. 

 

Did a masonry build but it's not an enjoyable experience to do it properly. 

 

The dense pack cellulose really helps with MBC and other TF builds. 

 

I would probably stick build and use cellulose next time. 

[saveasteading]

If I may confuse the issue.

I tried always to supervise air tests.

This because the attitude of the tester could vary between a quick test and disappear, or having a walk round to check for any open vents etc. And they never, ever offered to find a leak and test again (eg a vent fan that needed polythene over it.) 

One asked me what number I was looking for. I'm pretty sure I was never going to get a better figure than that.

 

On a tricky refurb the airtightness could never have been great but it was all the client wanted. There were no tests required. Later he had a test done to help rent the building, and I saw the report with clearly imaginary figures for insulation and airtightness 'as required'.

 

 

What am I  saying? Study the subject and supervise. Some trades will be contemptuous of airtightness, but that is part of managing the project.

For the test either find a small scale tester who will obtain the number you ask for, or use the best who will help improve the airtightness. Be present.

 

[SBMS]

2 hours ago, saveasteading said:

If I may confuse the issue.

I tried always to supervise air tests.

This because the attitude of the tester could vary between a quick test and disappear, or having a walk round to check for any open vents etc. And they never, ever offered to find a leak and test again (eg a vent fan that needed polythene over it.) 

One asked me what number I was looking for. I'm pretty sure I was never going to get a better figure than that.

 

On a tricky refurb the airtightness could never have been great but it was all the client wanted. There were no tests required. Later he had a test done to help rent the building, and I saw the report with clearly imaginary figures for insulation and airtightness 'as required'.

 

 

What am I  saying? Study the subject and supervise. Some trades will be contemptuous of airtightness, but that is part of managing the project.

For the test either find a small scale tester who will obtain the number you ask for, or use the best who will help improve the airtightness. Be present.

 

Agreed. We’ve already decided to use aerobarrier for the interim testing and then the actual sealing. They work for me the client (often the testers are getting whatever the builder needs them to get) so we will have this check and balance to ensure we get the level I’ve designed and want to achieve.