Shrinkage of engineered wood floor

[Jonny]

Hi Guys, 

Back last summer I fitted an engineered wood floor in a herringbone pattern. This was onto a levelled screeded floor and stuck on with f ball styccobond. 
 

Since I’ve been using the UFH more the planks appear to have shrunk/moved leaving a 1-2mm gap in places. 
 

Is this likely to settle/get worse/get better with UFH off? 
 

Any ideas? I’m quite tempted to fill in the gaps and re-oil the floor in the spring. 
 

Said floor:

[joe90]

Nice floor, what temp are you running the UFH?

[Jonny]

30 minutes ago, joe90 said:

Nice floor, what temp are you running the UFH?

Thank you, running at 35deg, the minimum it can be set at. 

[joe90]

Just now, Jonny said:

Thank you, running at 35deg, the minimum it can be set at. 

I think that is a tad warm, depends on your insulation and heat requirement but mine runs at 25’. Let’s see what others think!

[Jonny]

21 minutes ago, joe90 said:

I think that is a tad warm, depends on your insulation and heat requirement but mine runs at 25’. Let’s see what others think!

Hmm, the house is a Victorian terrace, solid walls, no cavity insulation, minimal loft insulation, however the new kitchen, has 150mm celotex in the slab, and 130mm flat roof construction. It’s always considerably warmer in the kitchen half of house. 
 

I actually can’t turn the blender down any lower on the UFH so unsure how I’d progress from here! 

[nod]

What temperature are your room stats set at 

[joe90]

2 minutes ago, nod said:

What temperature are your room stats set at 

I have one room stat in the hallway set to 20’.

[nod]

8 minutes ago, joe90 said:

I have one room stat in the hallway set to 20’.

That sounds similar to us 

We are at 18 throughout 

The factory setting is 22 which was to warm

 

 Before I tiled the ground floor I increased a degree each day with rooms tempts at 33 for one week in June 

Surprising how much the screed shrank 

[nod]

The problem with any wood is it will swell and shrink 
Im not sure that you can prevent this 

 

I’ve previously stated that I renovated two barns for Two joiners supposed forever homes 

Both asked me to tile the downstairs siting the same problems that your having 

They fit these floors for a living 

[Jonny]

12 minutes ago, nod said:

That sounds similar to us 

We are at 18 throughout 

The factory setting is 22 which was to warm

 

 Before I tiled the ground floor I increased a degree each day with rooms tempts at 33 for one week in June 

Surprising how much the screed shrank 

My kitchen stat is at 18 and rest of house at 21 (it’s draughty out of the kitchen!)

 

I think your right with the shrinking and swelling, the slight gaps are setting off my OCD - suppose I’ll just have to get used to it! 

[nod]

6 minutes ago, Jonny said:

My kitchen stat is at 18 and rest of house at 21 (it’s draughty out of the kitchen!)

 

I think your right with the shrinking and swelling, the slight gaps are setting off my OCD - suppose I’ll just have to get used to it! 

As a tiling contractor it would set alarm bells ringing 

But with a timber floor I wouldn’t give it a second thought 

Yours does look really good 

 

 

[joe90]

I have an engineered oak floor in the lounge over UFH, glued to the screed and that has not shrunk or moved at all. I did make sure the floor was completely dry and the oak sat in situ fir weeks before being fitted.

[newhome]

9 minutes ago, joe90 said:

I have an engineered oak floor in the lounge over UFH, glued to the screed and that has not shrunk or moved at all. I did make sure the floor was completely dry and the oak sat in situ fir weeks before being fitted.

 

Same here and it’s been down about 7 years. No problems with it upstairs either (laid over joists and UFH). 

[ProDave]

Another here with Engineered Oak over UFH. Into the second heating season and all the joints are still nice and tight.

[Jonny]

I too followed all advice, ie, screed was dried for over 7 months, flooring was acclimatised, temperatures slowly brought up once commissioned. I don’t know if it’s anything to do with the herringbone pattern? 

[PeterW]

Could be the pattern as it has shrunk unevenly across the length vs width. 

[joe90]

10 hours ago, Jonny said:

I don’t know if it’s anything to do with the herringbone pattern? 

I wanted herringbone but could not find what I wanted. Was offered a reclaimed a school floor but it was  too thick for UFH and cutting them all in half and scraping all the tar off was a job too far.

[PeterW]

1 hour ago, joe90 said:

I wanted herringbone but could not find what I wanted. Was offered a reclaimed a school floor but it was  too thick for UFH and cutting them all in half and scraping all the tar off was a job too far.

I have put 30sqm of parquet through a planer to take it down to 19mm which removed the tar and took it to a more reasonable thickness. 
 

Its 90 years old so I’m expecting that it should have shrunk by now and stabilised ... 

[Temp]

We have one or two joints in engineered oak that move with the seasons. They open in winter when the air is dry and close in summer when it's humid. I'm not sure I would fill any gaps in winter. 

[Nick1c]

@PeterW in our last house I found some 100 year old reclaimed Burmese teak strip flooring & used that over UFH. I couldn’t believe how much it shrinked, 3-4mm gaps between each strip, it was only 3” & 4” wide! With hindsight I would have laid it loose, cranked up the heat for a few weeks & then had it permanently fixed.