Mechanical Room Design

[KBK]

I was hoping to get some info on what would be a proper size room for a residential mechanical room. The house will be slab on grade, built out of ICF, 3800 sq ft, with 2 systems handling each side of the house. What is needed as far as door sizes, working room and room to set equipment with out it all being jammed in. Any other things that should be thought about as this is the design stage and I haven't been able to find anything about this. Thank you David

[okieair]

David there too many variables in the design of a system to just give you a square footage . Factors include unit dimensions, upflow/downflow, accessories like humidifiers or high efficiency air filters, duct design, conventional vs. geothermal, and state or local codes on access. There are even more things to consider that i'm not mentioning. You should have a detailed plan with all dimensions and design before beginning. But as a service man I sure do appreciate your thoughtfulness on not jamming it all into an undersize space. It will make all future repairs easier on us. That always tends to keep my attitude more pleasant than if i've spent twice as long squeezed into a rat hole trying to replace something that barely fits there by itself. Good luck.

[dan sw fl]

I was hoping to get some info on what would be a proper size room for a residential mechanical room. The house will be slab on grade, built out of ICF, 3800 sq ft, with 2 systems handling each side of the house. What is needed as far as door sizes, working room and room to set equipment with out it all being jammed in. Any other things that should be thought about as this is the design stage and I haven't been able to find anything about this.

David / FL

You likely only need ONE system for Each side of a 3,800 S.F. house.
TRY 12 foot x 12 Foot mechanical room for starters or use spray foam.

AIR HANDER UNITS are about 21" x 26" x 58 (52)"

Space planning would have to involve an actual duct layout.

http://www.trane.com/residential/pro...ableSpeed.aspx

2/4TEE3D40 40,000 3.0 52 26 21
2/4TEE3D49 49,000 4.0 58 26 21

Use spray foam ( http://www.zipfoam.com/ ) on the roof rafters with custom structure OR use SIPs and your mechanical room(s) can be elevated.

http://www.sips.org/

Zoning might be quite useful for special needs.
For example,
http://www.zonexsystems.com/aconsum.htm

[firecontrol]

If you know the footprint of ALL the equipment when installed, double the square footage. Take this number and multiply by 6.

[bmathews]

Check the codes before designing. We usually have to maintain at least 30" in front of the unit and anywhere that you will have to access. Electrical panels if you will have any require 30" of unobstructed access to them. Electrical disconnects also require that. Check for any clearances for gas as well. Keep in mind that you will have wires and pipes around the room and we really hate tripping over them on the way to service a unit. Consider floor drains beside the unit, that gets rid of unsightly pvc pipe everywhere. If really minimizes the amount you will need to trip over. Again, check with codes before doing anything. I've seen too many people go off half cocked only to get put in their place by an inspector when the final inspection comes and they won't pass and everything has to be un-done. You will also get charged to move everything back around by your contractor.

[KBK]

Thank you for the replies. I see that I need to work on getting more info on types of units and such. The ceiling deck will be concrete so no need to foam that area as the form system will already have it. I meant to say that there would be a system on each side of the house. I am interest in the zone systems, high efficient filter system and air exchanger due to this being an ICF house. Again thank you. david

[diesel65]

As big as you can make it !!

Seriously, once you figure out your equipment you will have a good idea of the size room you will need, just remember that you have to duct in the return now, so that is your air handler size space and the same again to accomodate your r/a duct, plus at least the depth of the equipment plus at least 30" for either the removal of the coil or whole macine if the need should arise.

I find it refreshing that you are taking the time to consider this as most people stuff it into the smallest hole they can then wonder why the duct is restricted or the cost of service is so high because of limited access, good for you.

[jibroni69]

If you know the footprint of ALL the equipment when installed, double the square footage. Take this number and multiply by 6.

I love your thinking, maybe make that 6 a 12 and go from there. The fact that a consumer is asking is probably the most fourthought that I have ever heard of. I love working in closets, not.