Garden Room to compliment new build

[Drew1000]

Hi,  Just finishing a new build with my son who has just moved in.  he wants to build a garden room approx 8M by 4M to use as a gym.  He has some pretty heavy equipment that he would like to put in so was thinking about a concrete floor probably around 100mm to 150 thick.  The plan is to install an air conditioning unit that would provide both heat and cooling.  Question I have is should I put something like 100mm celotex/Kingspan insulation under the concrete floor or would this be a waste of time and money.  The walls and ceiling will be well insulated.  Thanks in advance. 

[Faz]

You need to insulate the floor mate - I doubt you need 100 - 150mm screed either - he is not parking a tank on it!

[Marvin]

1 hour ago, Drew1000 said:

Hi,  Just finishing a new build with my son who has just moved in.  he wants to build a garden room approx 8M by 4M to use as a gym.  He has some pretty heavy equipment that he would like to put in so was thinking about a concrete floor probably around 100mm to 150 thick.  The plan is to install an air conditioning unit that would provide both heat and cooling.  Question I have is should I put something like 100mm celotex/Kingspan insulation under the concrete floor or would this be a waste of time and money.  The walls and ceiling will be well insulated.  Thanks in advance. 

I am working on the same thought with a client, and it came down to how much time it was going to be used and how much heat would be required.

 

In my opinion a raft foundation with a ring beam around the edge seemed about right to me. Being such a wide area means it could crack like a biscuit otherwise. Aim for the same sort of design as a single detached garage for the foundations.

 

But then you need to consider how often and how long used.

 

If the room is going to be left for 22 hours between uses I would be surprised if the concrete floor would warm up before your son was finished.

 

Thermal resistance of the walls, windows and roof need to be calculated. We have the rough shape. How tall? What's the makeup of the walls roof? Let the pedants talk of the heat produced by your son's training! I'm going to ignore it. 

 

Best 

 

Marvin

 

 

Edited August 7, 2021 by Marvin
Can't spell

[Ferdinand]

Wouln't it be reinforced (or with fibres) to prevent cracking?

 

Re: Biscuits.  Garibaldis don't crack, because they are reinforced with a layer of currants.

 

I am not clear what sort of 'garden room' you mean. Do you mean a garden building, or a garden room attached to the house?

 

In either case I would insulate below the floor, though only the 2nd may require it. I would also take great care with ventilation, and perhaps use a reversible single-point Heatpump as the air conditioning.

 

F

[SteamyTea]

1 hour ago, Ferdinand said:

Re: Biscuits.  Garibaldis don't crack, because they are reinforced with a layer of currants.

The currents are more the aggregate, but we all know they are squashed flies really.

1 hour ago, Ferdinand said:

or with fibres

The glutton can be considered a fibre as it is elastic and dispersed in the mix.

Though if they are wholemeal, the dark strands of fibre, that we are told are good for us, also acts as reinforcement.

 

Easier to just go for Nice biscuits, then dunk them in your tea.

[SteamyTea]

13 hours ago, Drew1000 said:

Question I have is should I put something like 100mm celotex/Kingspan insulation under the concrete floor or would this be a waste of time and money.

Do it, costs little and the usage of the shed may change in future.

11 hours ago, Marvin said:

If the room is going to be left for 22 hours between uses

This is where you want high thermal resistivity on the inside.  Control the air temperature rather than the fabric of the shed.

 

[joe90]

+1 for raft with thicker ring beam and steel mesh fir piece of mind. Regarding heating / insulation if it’s a gym then why? He will (should) be producing his own heat!, if a garden room then that’s different. A decent fan heater would warm that up fairly quickly.

[SteamyTea]

49 minutes ago, joe90 said:

A decent fan heater would warm that up fairly quickly.

Yes, by far the most cost effective way.

Regarding the gym equipment, while they seem heavy, the static load is fairly low. The dynamic load is the problem.

[Ferdinand]

41 minutes ago, SteamyTea said:

Yes, by far the most cost effective way.

Regarding the gym equipment, while they seem heavy, the static load is fairly low. The dynamic load is the problem.

 

Translated.

 

Movement and people jumping up and down and dropping things. ?

[TonyT]

I would make the slab the same thickness all the way around, far easier to construct a shutter and install 2 layers of mesh than muck about with different depth.

me I would go for 8” concrete slab c35 with mesh  just under 7 cubic metres.

[SteamyTea]

17 minutes ago, Ferdinand said:

Translated

Energy is Half mass times velocity squared.

Momentum is Mass times velocity.

Force is Mass time acceleration.

 

That should cover it as no need to worry about vectors.

[Ferdinand]

1 hour ago, SteamyTea said:

Energy is Half mass times velocity squared.

Momentum is Mass times velocity.

Force is Mass time acceleration.

 

That should cover it as no need to worry about vectors.

 

Observed the Beeboid commentator on the Madison last night remarking on a "transfer of speed" when they did the hand-sling.

 

You have some work to do ?.

 

Now, back to topic...

[SteamyTea]

6 minutes ago, Ferdinand said:

transfer of speed

That will be an acceleration then.

A change in speed (scalar) or a change in direction is acceleration.

Acceleration is either positive or negative, once direction is taken into account.

Though it could be a momentum change if one rider gave a shove to another. One gains as the other looses.

Energy cannot be created and momentum is always preserved in classical physics.