Sports court rubber flooring

CKJ

I am having an indoor sports court (30 x 44 x 22 ft built with in floor heat but I would also like to put down a thick rubber flooring to keep my old knees from hurting and to cushion the falls my kids will inevitably have. I was looking at a 12 mm rubber underlayment and then actual flooring that is 5mm of rubber bound to 2 mm vinyl on top. Would this be a horrible idea in terms of the heating having to go through that amount of rubber?  I live in South Dakota and haven’t been able to find a flooring person who can tell me if it’s reasonable or not. Speed of heating the room isn’t an issue as it’s a sports court not living space, I just want to make sure I’m not killing the efficiency of the system by using such a high R value flooring system. All of your opinions are much appreciated!

Mad Dog_2

Whatever company is installing needs to know this via the PEX manufacturer he uses AND the rubber matting manufacturer.  We've done in gymnasiums and it works fine even with low supply temps. But he'd better start with a heatloss and go from there. Mad Dog 🐕 

realliveplumber

What is the R value of the floor system?

WMno57

Forced air would give you the option for AC. You could still have radiant installed in the slab. If the building had forced air heat, the radiant could be set to a lower temp.

Jamie Hall

Contact the flooring manufacturer for the maximum rated temperature of the material...

Derheatmeister

Depending on density of Rubbermats it will reduce your heat transfer..
How about using Radiant walls ?
You can get more BTU/HR per Sqft output and will not have to worry about offgassing / reducing your efficiencies..

hot_rod

There were some hard rubber "radiant" carpet underlayments available years back. They were around 0.6 r-value in 1/2" thickness.

CKJ

Looking up R values for the recycled rubber underlayment it is about 1.1 and For the flooring that is 5 mm recycled rubber and 2 mm vinyl I don’t have an r value but assume it would be about .5 for the rubber and .15 for the vinyl. 

Thought about radiant walls but it seems like the size of the room has a lot of space relative to the wall surface (30 x 44 x 20-24 ft W x D x H). Also we are in SoDak so it will not uncommonly be -30 or -40 outside with the windchill. 

Also want to really thank everyone that is commenting, it is much appreciated!

hot_rod

1320 sq ft X 27 btu/ sq ft from radiant walls is workable . A 35,000 load, just guessing?

You probably don’t beed 72 degree temperature? Maybe 66-68 degrees? That helps the load number and the radiant output,

I would think you want some air movement in a room like that?  So a small ducted system with some cooling capacity and assist for quick heat start up, perhaps

you need a load number and that should be a simple room to calculate

Jamie Hall

What @hot_rod said above. I'm really concerned about your being able to get enough heat out of that floor at temperatures which the rubber can tolerate.

Also, I wouldn't be too concerned about the R value of the rubber. Provided the floor is adequately insulated below and at the perimeter, all that will happen is that the floor will have to run a little hotter (but see above) and will respond slower.

jblum

The basic question is what floor surface temperature is needed to maintain the space at a temperature suitable for its intended use during the cold months. The appropriate ambient air temperature to use for design purposes depends what comfort level is expected. I would design the heating for 68F ambient temperature to allow the space to be used for non-athletic purposes if desired. An allowance is system sizing in case actual air leakage and R-values are worse than expected.

hot_rod

The lower you can run the ambient, the higher BTU/ sq ft you can get from the floor, also.

Tim_D

With the rubber floor covering assembly giving an R-2, a 68f room set point, a 4" concrete slab with r-10 under slab insulation, 1/2" PEX at 6" on center would give you 32 but/sqft with a 140f supply water temperature.

CKJ

Just wanted to thank everyone for your time knowledge and comments. I will post an update once we get the project up and running. Thanks again!