lots of cracks after attic floored

[Barryscotland]

Bungalow with attic trusses for future development was built, finished, after a year or so snagging of decor done and a few cracks in ceiling along tapes and screw pops fixed. another 6 months later the attic was floored and within a few weeks cracks started to appear in ceilings which we expected a few of but every room has multiple and some are a few mm wide, theres even a few starting in the upper edges of room walls. Upstairs isn't in use its just storage.

 

Question is should we be concerned and if we wait another 6 months and have the tapes fixed and redecorate is it going to continue to happen?

[ToughButterCup]

I think this is another of those -pics-please- questions Barry.....

[Mr Punter]

As it is only for storage I would wait at least 6 months before doing anything.  The timber will shrink across the grain as it dries and this can cause cracking.

[Barryscotland]

There’s 25+ cracks 

[MikeGrahamT21]

I’m no professional plasterer but that looks like someone forgot the scrim when it originally got done

[Barryscotland]

On 06/12/2023 at 21:29, MikeGrahamT21 said:

I’m no professional plasterer but that looks like someone forgot the scrim when it originally got done

Whats scrim?

 

Plasterboard joins where taped, skimmed over then rubbed down before painting

[Barryscotland]

On 06/12/2023 at 18:07, Mr Punter said:

As it is only for storage I would wait at least 6 months before doing anything.  The timber will shrink across the grain as it dries and this can cause cracking.

 

Do you mean the chipboard flooring will shrink? Attic trusses have surely done most of there shrinking 

[Mr Punter]

4 minutes ago, Barryscotland said:

 

Do you mean the chipboard flooring will shrink? Attic trusses have surely done most of there shrinking 

 

Yes the trusses, noggins, rim boards and all the timber frame members.

[Kelvin]

You’ve just added a lot of extra weight into the building so it’s likely caused some movement of the timbers. 

[MikeGrahamT21]

2 hours ago, Barryscotland said:

Whats scrim?

 

Plasterboard joins where taped, skimmed over then rubbed down before painting

 

Its the mesh tape you use in between the joints. Do you know what kind of tape was used? You should be able to see the tape where the cracks are if its in there, shine a light in it

[Barryscotland]

On 08/12/2023 at 13:20, MikeGrahamT21 said:

 

Its the mesh tape you use in between the joints. Do you know what kind of tape was used? You should be able to see the tape where the cracks are if its in there, shine a light in it

It was the mesh tape, but all missing the point here, its been fine with next to zero crackage for nearly two years, what little crackage there was was fixed after a year. since the attic was floored 3 months ago about 30percent of all ceiling joints have cracked open. 

[joe90]

On 06/12/2023 at 11:19, Barryscotland said:

Bungalow with attic trusses for future development was built,

Having read all the above it strikes me that the trusses are not fit for the extra loading, you say “for future development” can you expand on that @Barryscotland

Edited December 18, 2023 by joe90

[jamiehamy]

5 minutes ago, Barryscotland said:

It was the mesh tape, but all missing the point here, its been fine with next to zero crackage for nearly two years, what little crackage there was was fixed after a year. since the attic was floored 3 months ago about 30percent of all ceiling joints have cracked open. 

The weight of the boards will have certainly contributed, along with the weight of a person moving about up there and whatever you have being stored. If the joists were not designed for an additional dead weight and active weight (or whatever the technical terms are!), then deflection will certainly occur (which it would regardless), and this will cause cracking at joints. 

 

If they were designed to be (in effect) habitable, or to have weight bearing, then this is a problem, but if not, then I'd recommend against storing anything else and contemplate taking everything out before you redo the joints. 

 

 

 

 

[Kelvin]

50 minutes ago, Barryscotland said:

It was the mesh tape, but all missing the point here, its been fine with next to zero crackage for nearly two years, what little crackage there was was fixed after a year. since the attic was floored 3 months ago about 30percent of all ceiling joints have cracked open. 

We really aren’t missing the point. It was fine until something changed. That change was adding a lot of extra weight onto the timbers. If the timbers had some space between them (that weren’t filled with packers say) then they can move. Even very small movements will crack plaster. I went around all my first floor timbers and packed out any narrow gaps with thin bits of wood and glue for example. 

[saveasteading]

Stiffening the attic space, as you have done by boarding it,  can cause cracking elsewhere because everyday movement is limited. 

Ie it used to all move a bit, but now that crack is between the original construction and the new.

[Barryscotland]

4 hours ago, joe90 said:

Having read all the above it strikes me that the trusses are not fit for the extra loading, you say “for future development” can you expand on that @Barryscotland

there attic trusses so are designed to be turned into a liveable space and take the weight, "for future development" the house has been designed to develop the upstairs into a habitable space in the future.  

[MikeGrahamT21]

24 minutes ago, Barryscotland said:

there attic trusses so are designed to be turned into a liveable space and take the weight, "for future development" the house has been designed to develop the upstairs into a habitable space in the future.  

what size are the horizontal timbers of these trusses that form the loft floor/room ceiling?

[Barryscotland]

11 minutes ago, MikeGrahamT21 said:

what size are the horizontal timbers of these trusses that form the loft floor/room ceiling?

 

they are 7"

[MikeGrahamT21]

34 minutes ago, Barryscotland said:

 

they are 7"

and thickness?

[joe90]

This still sounds to me like the trusses are not “fit for purpose” or installed properly. On my build the roof was not built for future development (not trusses but “I” joists) and that was boarded out and loads of stuff in storage plus working up there to complete the house and NO cracks appeared in the following 4 years .

Edited December 18, 2023 by joe90