Timber I beam construction longevity.

[gavztheouch]

I am considering an eden insulation or similar build. Specs are as follows 300mm Ibeam, blown insulation, plastic coated OSB3 vapour barrier and airtightness layer, wood fibre insulation board on outside. Clad externally with wood.

 

My worry is water ingress causing damage to the wall through detailing mistakes, building error or just bad maintenance.

 

My thinking is a wall construction like this would be more susceptible to water damage with the engineered timber and high airtightness levels than say a traditional less insulated stick built home. If the wall was damaged I'm struggling to see an easy way to repair it because of the way it is constructed.

 

How long do you think a house like this would survive, could the design of the wall and roof be modified to be an easier repair in the future?

[MikeSharp01]

If you can keep it dry - you are right everything is in the detailing, and you don't set fire to it then it should last 100 years plus. Timber buildings can last 100s of years and many have. 

 

 

[nod]

Modern timber framed houses are nothing like the old Tudor buildings that have stood the test of time 

The TF have only been about since the 70s It doesn’t inspire confidence when manufacturers quote 30 40 year lifespan for the frame 

 

I worked on some Student accommodation about fifteen years ago They where being sold off in pods of 8 Which seemed a great investment We pulled out of buying at the last minute due to this 30 to 40 year being banded about 

[scottishjohn]

21 minutes ago, nod said:

Modern timber framed houses are nothing like the old Tudor buildings that have stood the test of time 

The TF have only been about since the 70s It doesn’t inspire confidence when manufacturers quote 30 40 year lifespan for the frame 

 

I worked on some Student accommodation about fifteen years ago They where being sold off in pods of 8 Which seemed a great investment We pulled out of buying at the last minute due to this 30 to 40 year being banded about 

myTF house was built in the 70,s and no sign of it fallng down or rotting away ,or indeed house values of these early houses being effected by thier age 

 so providing built correctly I see no fixed life for them ,no more than they say brick houses etc have a 60 year life span 

 

[Oz07]

I think op is specifically talking high performance frames where vapour barriers and condensation points etc etc 

[nod]

56 minutes ago, scottishjohn said:

myTF house was built in the 70,s and no sign of it fallng down or rotting away ,or indeed house values of these early houses being effected by thier age 

 so providing built correctly I see no fixed life for them ,no more than they say brick houses etc have a 60 year life span 

 

Who ever says that is wrong 

The difference with masonry homes is there are ten of thousands of home over a hundred years old 

Just Googled life span of a new built masonry house 

Cane back as over a hundred years

 

 

[Patrick]

Got a point there. Question really is, what do you want from your house?

If it's longlivety then this would be the best choice :

 

Not very comfortable. A nightmare in heating costs. But will last 1000++years.

Insulation in general is a bad idea.

From a lifespan perspective. But I still wouldn't want to life in a house without it.

As my favorite Building Scientist Joe Lstiburek said : every bit of engineering you put into a Building will compromise it s lifespan. (careful. Generalisation)

 

[Thedreamer]

29 minutes ago, nod said:

Who ever says that is wrong 

The difference with masonry homes is there are ten of thousands of home over a hundred years old 

Just Googled life span of a new built masonry house 

Cane back as over a hundred years

 

 

 

Is there a difference between a masonry home constructed with light weight block and dense concrete block? We used a few lightweight blocks and were surprised how crumbly they were compared to the dense concrete block we used for the blockwork external skin. 

Edited December 10, 2019 by Thedreamer

[joe90]

Personally I don’t like lightweight blocks, I used heavy blocks fir my inner skin and can hang anything off it with no probs. I have seen a few walls using lightweight blocks that have cracked badly (possibly built wrong?).

[SteamyTea]

8 hours ago, nod said:

Modern timber framed houses are nothing like the old Tudor buildings that have stood the test of time 

 

I have heard the same argument about old cars, that must be why I am surrounded by Morris Minors, Austin Minis, Ford Populars...

It is amazing how the ghost of Barrett Homes is still with us.  The World In Action expose was in 1983.

[Oz07]

7 hours ago, joe90 said:

Personally I don’t like lightweight blocks, I used heavy blocks fir my inner skin and can hang anything off it with no probs. I have seen a few walls using lightweight blocks that have cracked badly (possibly built wrong?).

Are we talking airated or lightweight conc?

[Gone West]

10 hours ago, nod said:

The TF have only been about since the 70s It doesn’t inspire confidence when manufacturers quote 30 40 year lifespan for the frame 

The timber framed bungalow, that I dismantled last year, was built in 1920s as a temporary house for homes for heroes after WW1. It was stick built on site and made of 4" x 2". It was still standing and the only localised rot was due to later 1950s modifications.

[joe90]

2 hours ago, Oz07 said:

Are we talking airated or lightweight conc?

 

Not sure as I have limited knowledge, I have just worked on properties with airated/lightweight blocks and found them “horrible “. I did a loft conversion for my mate and his gable inner walls had to be rebuilt as they were cracked and falling apart (blocks and mortar). The only blocks I found reasonable were Celcon (airated?), I was not laying them but fitting out to them.

[joe90]

1 hour ago, PeterStarck said:

The timber framed bungalow, that I dismantled last year, was built in 1920s as a temporary house for homes for heroes after WW1. It was stick built on site and made of 4" x 2". It was still standing and the only localised rot was due to later 1950s modifications.

 

The bungalow we replaced was built about 1940s, timber was mostly ok but the sole plate had completely disappeared with rot due to the high water table round here.

Edited December 11, 2019 by joe90

[scottishjohn]

41 minutes ago, joe90 said:

gable inner walls had to be rebuilt as they were cracked and falling apart (blocks and mortar). The only blocks I found reasonable were Celcon (airated?), I was not laying them but fitting out to them.

I suspect these were built before the requirement for expansion joints in block work .

seen plenty of cracks due to that 

[joe90]

14 minutes ago, scottishjohn said:

I suspect these were built before the requirement for expansion joints in block work .

seen plenty of cracks due to that 

 

Frankly the gables were not big enough to require expansion joints.

[epsilonGreedy]

1 hour ago, joe90 said:

Not sure as I have limited knowledge, I have just worked on properties with airated/lightweight blocks and found them “horrible “.

 

 

The forum needs a good definitive reference thread on blocks. When I was starting out in self build I wasted hours online trying to comprehend the scope of blocks available and their pro's and con's. 

[Patrick]

9 hours ago, epsilonGreedy said:

 

The forum needs a good definitive reference thread on blocks. When I was starting out in self build I wasted hours online trying to comprehend the scope of blocks available and their pro's and con's. 

word!

[Oz07]

Surely you can all figure out airated. Its the type that look like a aero chocolate bar with bubble like appearance. There are various manufactures which make them hence different product names celcon took its etc. 

 

Lightweight conc, sense conc then isn't there like a hybrid light conc with expanded clay @PeterW @Brickie @Declan52 ? 

 

I've used ultralytes on latest place 

[Oz07]

*toplite etc

[kxi]

Some more block examples ordered by density (not comprehensive and updated last year)

https://docs.google.com/spreadsheets/d/1FKs4IIEIqb-KFJl63zsR0uj2BXAnEJMyyQbyeiZNylc/edit?usp=sharing

 

@Oz07 expanded clay examples: fibolite, fibo 850, aglite ultima

 

[scottishjohn]

21 hours ago, joe90 said:

 

Frankly the gables were not big enough to require expansion joints.

maybe the blocks were wet onsite before errection --then froze --breaking them up  to start with 

all these type of aero blocks ,must not get wet +frozen or they loose integrity over time 

[Declan52]

13 hours ago, Oz07 said:

Surely you can all figure out airated. Its the type that look like a aero chocolate bar with bubble like appearance. There are various manufactures which make them hence different product names celcon took its etc. 

 

Lightweight conc, sense conc then isn't there like a hybrid light conc with expanded clay @PeterW @Brickie @Declan52 ? 

 

I've used ultralytes on latest place 

I just used standard lightweight blocks on all my inside skin of my cavity . When you cut them you could see everything from glass to ash instead of normal aggregate to keep the weight down.

As long as you soak them prior to wet plaster being applied then they won't suck all the moisture out of the wet plaster and cause the wall to crack.

[gavztheouch]

Opinion thought on the idea of a 2x6 wall with say 150mm of external insulation. Benefits of no osb I beams, you should see internal water leaks coming through onto the plaster board as there would be no insulation between the studs to trap water and your service cavity would be well away from the air barrier on the outside of the frame. If not going for passive house does this sound more robust than a blown cellulose iBeam construction?

[ProDave]

1 hour ago, gavztheouch said:

Opinion thought on the idea of a 2x6 wall with say 150mm of external insulation. Benefits of no osb I beams, you should see internal water leaks coming through onto the plaster board as there would be no insulation between the studs to trap water and your service cavity would be well away from the air barrier on the outside of the frame. If not going for passive house does this sound more robust than a blown cellulose iBeam construction?

Why would you have no insulation between the studs?  do you want a cold house?

 

The VCL would surely go on the inside of the frame? (mine is as I think everyone else)