Building a straw bale house on the western side of Islay

[Selina]

Hello, 

in my research I have noticed that the Scottish Islands don’t really have straw bale houses unless they’re lets. I want to know if anyone here has an idea as to what the challenges are. I’m keen to build a straw bale on the Rhinns of Islay (primarily) or elsewhere on the islands stand. 
thanks

Selina

[ProDave]

Wind driven rain will be your greatest challenge there.

[Onoff]

The story of the Three Little Pigs springs to mind!

[joe90]

I too was keen on straw bale a few years ago but didn’t go ahead with that for various reasons, yes wind driven rain will be a real problem up there in my opinion. Straw bale started in dry America mostly. I was going to build a scaffold shell to build mine in so it was rain protected until the lime render was completed,I went with brick and block in the end as it was more acceptable to mainstream building methods.

Edited Tuesday at 18:27 by joe90

[SteamyTea]

There are 2 types of straw bail buildings.

Structural and non structural.

 

Both are expensive to build, poor performing, not environmentally good and will give you long term issues.

 

Build from timber with modern insulation materials and plastic based vapour and air control layers.

[saveasteading]

If this is a proper house then I'd advise against straw on Islay.

I recall a grand designs, I think it was. It was in or near less exposed London yet the outer face was  dishevelled, brown and yeuch. 

The architect/ owner loved that it was reacting with nature....or rotting and a home for creatures  as most would describe it.

Around that time I knew a few academics who wanted to use straw. 20 years on and it has rightly not become a mainstream process.

When most buildings are designed for a 50 year life, we expect 100. With straw, 30?

It's fashionable  for the rich or a necessity for the poor.

 

[Iceverge]

Just now, SteamyTea said:

There are 2 types of straw bail buildings.

Structural and non structural.

 

Both are expensive to build, poor performing, not environmentally good and will give you long term issues.

 

Build from timber with modern insulation materials and plastic based vapour and air control layers.

 

I would argue the toss on this.

 

I would say there's nothing too modern about blown cellulose, EPS or mineral wool. 

 

I'd take them any day of the week over PIR, Phenolic or Aerogel insulants. 

 

 

[SteamyTea]

1 minute ago, Iceverge said:

would say there's nothing too modern about blown cellulose, EPS or mineral wool

Well grasses have been around a few million years. Concrete/brick maybe 5000 years.

Plastics since the 1907, or 6 years after my grandmother was born, and only 22 years before my mother's birth.

So I suppose it depends on your idea of modern.

[Iceverge]

5 minutes ago, SteamyTea said:

Both are expensive to build, poor performing, not environmentally good and will give you long term issues

 

Agreed. 

 

As a structural material or an insulant bales bring lots of issues. 

 

Nothing is Impossible, but to get a high performance straw house will be much more expensive than alternative methods. Especially on an island with very high winds, rainfall levels and straw bales that will need to be sourced hundreds of miles away. 

 

As an insulation material alone I actually like straw. It can be installed as a blown product in a similar fashion to cellulose. At a guess it has less environmental issues as the access to second hand newspapers for cellulose to recycle is diminished and more virgin paper is pulled into manufacturing. 

 

https://www.iso-stroh.ch/en/

 

I don't know if anyone doing it in the UK or Ireland though. 

[Iceverge]

3 minutes ago, SteamyTea said:

Well grasses have been around a few million years. Concrete/brick maybe 5000 years.

Plastics since the 1907, or 6 years after my grandmother was born, and only 22 years before my mother's birth.

So I suppose it depends on your idea of modern.

 

Reminds me of my cousin who is a geologist and has a very different take on climate change to most people. 

 

He can't believe how short term our perspective is, but then he largely deals in Eras. 

 

 

[Iceverge]

@Selina

 

Here's is what I would consider to be a higher quality straw bale house although in reality it is a timber house with bale insulation. 

 

https://passivehouseplus.ie/magazine/new-build/norfolk-straw-bale-cottage-aims-for-passive

 

However it relies solely on external render for rain protection. 

 

I wouldn't consider that wise in Islay which has about twice the rainfall of Norfolk and much of it horizontal. 

 

 

[Iceverge]

https://oldholloway.wordpress.com/2016/09/

 

Another way to use straw as a building material although it really is a timber house with straw insulation. One of my favourite houses though but I think I would stick build it instead and blow in cellulose. 

 

Not without it's risks though. Cost, long supply chains, and the issue of the walls starting to grow if they get wet in the building process. 

 

 

Edited Tuesday at 19:05 by Iceverge

[Redbeard]

What about pre-fabricated straw panels?

 

"If you’d like to get in touch with Barbara about consultancy, EcoCocon’s prefabricated panels, or anything else, you can email her at barbara@strawbuilding.org.uk or contact her by phone on 07720 716 589."
 

[saveasteading]

43 minutes ago, Iceverge said:

straw bales that will need to be sourced hundreds of miles away

I wouldn't think it's that far. Ayrshire will have lots, and there's probably plenty at half that distance.  

And Islay's incredible whiskies started as barley...from where?

 

But I'm distracted.   

[gavztheouch]

1 hour ago, Redbeard said:

What about pre-fabricated straw panels?

 

"If you’d like to get in touch with Barbara about consultancy, EcoCocon’s prefabricated panels, or anything else, you can email her at barbara@strawbuilding.org.uk or contact her by phone on 07720 716 589."
 

EcoCocons Panels look good. 

 

This house was built with them https://www.passivhaustrust.org.uk/projects/detail/?cId=88

 

 

[Russell griffiths]

Don’t do it, silly idea, leave it to the idiots on some random tv programme. 
there are far better building methods out there. 
and far better things to use regarding your location. 

[Selina]

Thank you all for your input. There’s lots of food for thought. I’ll look into the timber frames. There are some misunderstandings about proper straw bale construction. A properly built house should last 100-200 years. 
I did see a person using a poly tunnel to store his straw while he built. Ensuring it was kept dry. Yes the straw is the insulation and there is a frame around it. The houses are eco friendly and can be off grid sustainable. 
Straw is a byproduct of farming and currently has no reuse except for insulation (so far that I know), so it’s being recycled and not taking away from the food chain. The straw bale house will be sealed in lime plaster, or similar material to create an anaerobic environment. I intend to clad it in rock keeping with the home blending into the environment. And being more traditional in appearance. A lot of the building materials are sourced from Islay, keeping the cost of importing supplies from the mainland down. I’m also sourcing an experienced construction firm to help with the build. 

[Russell griffiths]

Using stone as an external skin sounds fine, it’s the bales and lime render on the outside I didn’t like the sound of. 
straw bale house wrapped in traditional stone, why not, now it’s explained a bit more it seems perfectly reasonable. 

[SteamyTea]

29 minutes ago, Selina said:

Straw is a byproduct of farming and currently has no reuse except for insulation

It has many uses. Animal bedding, soil conditioning, even strawboard manufacture.

 

31 minutes ago, Selina said:

not taking away from the food chain

That is an interesting area. If the 'food' part is turned into cattle feed, then it is a very wasteful use of land.

About a third of the UKs productive farmland is not currently farmed, rewilded or used in any productive capacity. Farmers don't let on about that but the FAO data shows otherwise.

[joe90]

37 minutes ago, Selina said:

I intend to clad it in rock

 

7 minutes ago, Russell griffiths said:

Using stone as an external skin sounds fine, it’s the bales and lime render on the outside I didn’t like the sound of. 

The lime render turns into limestone. There was a picture on the internet some years ago after the California fires and the only thing left standing were the walls of a straw bale house. Straw is an excellent recycled material. Just needs to be kept dry whilst building (hence my plan to create a scaffold and clad shell during the build).

[saveasteading]

Wildfires are unlikely on Islay I'd think.

 

So it seems that the straw is only for wall insulation.

What thickness will that be? It will either reduce floor space or require additional footprint.

Either might be considered in analysing the cost in money and carbon.

 

Might it be feasible to build a proven structure, and fill the voids with compressed straw instead of commerical insulation. It wouldn't be enough but it would tick that box.

 

Internal walls will be in conventional material presumably.

 

Some thoughts on straw:

 

There used to be a concrete block containing straw. I think it was  a cheap bulker rather than for its properties.

Straw is about half the height it used to be, through breeding,

I once used straw bales under a deeply buried sewer. It was a recognised means of carrying load over soft ground.

It works nicely as thatch although reeds seem to be better. But the slope makes that work.

 

From a quick search it seems that straw has a value, ie is not always waste.

This needs a farmer to advise.

 

[joe90]

53 minutes ago, saveasteading said:

What thickness will that be?

Small bales typically used are 18” so only 2” more then my brick and block walls with 200mm filled cavity.

53 minutes ago, saveasteading said:

Wildfires are unlikely on Islay I'd think.

My point was people fear straw as flammable ( it’s only a problem during the build with bits of loose straw lying about. A compressed bale is a bit like a telephone directory, difficult to set fire too and once lime rendered inside and out bomb proof).

53 minutes ago, saveasteading said:

Might it be feasible to build a proven structure, and fill the voids with compressed straw instead of commerical insulation.

Straw bale is used in two basic styles of construction: “Nebraska”-style structures, which resemble Southwestern adobe-style architecture and use the straw for structural support; and post-and-beam construction, with straw-bale infill for insulation. Some structures incorporate both of these styles.
 

53 minutes ago, saveasteading said:

It wouldn't be enough but it would tick that box.

Not sure of the U value of straw but at 18” it must be pretty good.

 

mind you I changed my mind and built in brick and block in the end, mostly because at my age I paid a main contractor to do the heavy work 🤷‍♂️

Edited 12 hours ago by joe90

[Onoff]

1 hour ago, joe90 said:

Straw is an excellent recycled material. Just needs to be kept dry whilst building (hence my plan to create a scaffold and clad shell during the build).

 

When I build my pallet shed, I wonder what value I could end up with if I packed the pallet walls with straw?

 

Might be best not to do the shou sugi ban charring with the cladding fitted.....

 

 

(My nephews shed, not mine). 

[SteamyTea]

 

[ChrisInKent]

It also matters if you’ve got the cash to build it in full, need a mortgage on it now or in future or need it to be an asset you could sell if you had to. If none of that matters ignore the rest below.

If you need to sell it would it be mortgageable or require a cash only buyer? Our timber frame with 100% metal cladding reduced mortgage providers to 2.  Look at the challenges Colt houses have selling just 60 years later - cash only. Will a mortgage company believe the 100-200 years or be totally risk averse. You can build anything but it’s whether you need it still to be an asset in your lifetime or not and can persuade lenders of that.