Concrete floor come away from wall

D

D14

Member

• Jun 14, 2018

• #1

We put a new floor into an existing grain shed 3 years ago and due to shrinkage theres a gap about 3cm wide all the way around. We've tried putting cement into it but the grain bucket lifts it away once its become brittle. Any ideas of something better? Concrete isn't any option because the gap isn't big enough for it to bind together and a local concrete guy has had a look saying he'd need to cut away about 2ft for it to stand a chance and even then he wasn't keen.

 

Last edited: Jun 14, 2018

Steevo

Member

Location

Gloucestershire

• Jun 14, 2018

• #2

10cm? That seems a huge amount.

I've had floors shrink about 1-2cm and just filled those with panel mastic. Works well and stays flexible in case of further shrinkage/expansion. Could work out expensive if filling 4" wide gaps though.

 

D

D14

Member

• Jun 14, 2018

• #3

Steevo said:

10cm? That seems a huge amount.

I've had floors shrink about 1-2cm and just filled those with panel mastic. Works well and stays flexible in case of further shrinkage/expansion. Could work out expensive if filling 4" wide gaps though.

Click to expand...

Typo now corrected. 3cm average.
I tried the panel mastic initially but it didn't seem to stick very well and when dried was like a window wiper blade.

 

Dry Rot

Member

Livestock Farmer

Location

Scottish Highlands

• Jun 14, 2018

• #4

Do you not need to paint the edges with cement/water mix to get a bond?

 

D

D14

Member

• Jun 14, 2018

• #5

Dry Rot said:

Do you not need to paint the edges with cement/water mix to get a bond?

Click to expand...

Tried that before last harvest and now its all opened up again.

 

SeatWarmer

Member

Location

Berwickshire, Scottish Borders

• Jun 14, 2018

• #6

I agree with Steevo, panel mastic is a good option, depending on area size though.

As for your grain bucket pulling the cement out, if you have a bucket where the wearing edge is wider than the bucket itself, cut it back flush with the sides. I've had this problem before with a shed that was once used as a silage pit and had wooden sleepers on one side wall, the wearing edge would get under the bottom sleeper when scraping tight to the edges and lift the whole lot up.

 

Badshot

Member

Location

Kent

• Jun 14, 2018

• #7

I had this problem, it wasn't shrinkage though, the walls were pushing out as the walls weren't tied into the floor.
No one could tell me how to stop it happening so I attached another barn to it and concreted it properly
The gap was increasing every year, it's now stopped.
Get a long straight edge and spirit level, you might be surprised by how far out of upright the stanchions are.

 

D

D14

Member

• Jun 14, 2018

• #8

Badshot said:

I had this problem, it wasn't shrinkage though, the walls were pushing out as the walls weren't tied into the floor.
No one could tell me how to stop it happening so I attached another barn to it and concreted it properly
The gap was increasing every year, it's now stopped.
Get a long straight edge and spirit level, you might be surprised by how far out of upright the stanchions are.

Click to expand...

We've checked them and its definitely the floor as its also coming away from a central concrete panel wall. Apparently concrete mixes with fibres in for strength shrink more than basic concrete. Its also got underfloor tunnels in it that are sending heat which hasn't helped matters.

 

Badshot

Member

Location

Kent

• Jun 14, 2018

• #9

D14 said:

We've checked them and its definitely the floor as its also coming away from a central concrete panel wall. Apparently concrete mixes with fibres in for strength shrink more than basic concrete. Its also got underfloor tunnels in it that are sending heat which hasn't helped matters.

Click to expand...

Keep an eye on it.
The floor on the new barn hasn't shrunk more than 5-10mm.
, in fact I don't think there's a gap along the concrete panels at all.

 

Dry Rot

Member

Livestock Farmer

Location

Scottish Highlands

• Jun 14, 2018

• #10

You could always give this organisation a ring and see if they can offer advice. All it would cost is a phone call.

https://www.thenbs.com/

 

Exfarmer

Member

Location

Bury St Edmunds

• Jun 14, 2018

• #11

Dow corning C60 its amazing stuff.
After applyication use a finger covered in a suitable glove dipped ina fairy liquid mix to smoothe off

 

H

HBush

Member

• Jun 15, 2018

• #12

Badshot- You are not the only one to find the wall moving away from the floor. This has happened in my shed when mucking it out. A pity that I do not have room for a shed on the other side though.

 

RWG Contracts

Member

Location

Samlesbury, Lancashire

• Jun 15, 2018

• #13

D14 said:

We put a new floor into an existing grain shed 3 years ago and due to shrinkage theres a gap about 3cm wide all the way around. We've tried putting cement into it but the grain bucket lifts it away once its become brittle. Any ideas of something better? Concrete isn't any option because the gap isn't big enough for it to bind together and a local concrete guy has had a look saying he'd need to cut away about 2ft for it to stand a chance and even then he wasn't keen.

Click to expand...

You want this

http://www.fosroc.com/product/show/renderoc-gp-

 

Dman2

Member

Location

Durham, UK

• Jun 18, 2018

• #14

we poured hot tar into a gap in one of our buildings
Been there a lot of years now