Mechanical Room Size Considerations
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We’re still in the never ending design stage of our retirement home and I’m trying to get my head around the details on the mechanical room. I intend the room to house the washer and dryer with room for small work table and hanger bar, water heater (with manifold assy), electrical panel (if allowed), and air handling system (ERV, etc.). Trying to figure the best way to figure out the dimensions needed. Keep in mind that I haven’t decided on equipment yet so I know that will effect the dimensions.
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Replies
That's right. You never know how big of a sack you need until you've figured out which beans are actually going into it.
Was there a question?
Yes there was. :) Other than footprint of the equipment we decide on and room to move around said equipment, what other considerations should we consider?
Our mechanical room is about 9x10'. Stacked washer/dryer, upright freezer, utility sink, well expansion tank, electrical panel, solar inverter, water heater. HRV on ceiling. Few shelves for cleaning stuff. Plenty of room.
If you got space to spare, access from 3 sides for major equipment, ERV near the outside wall. Make sure there is enough room to change filters.
Floor drain if you have condensing burners. Plenty of power outlets and good lighting.
I managed to fit a furnace with AC coil, ERV, stacking washer/dryer and the bathroom plumbing manifold in a 24" x 28" closet... And it still is a nightmare to deal with...
My 2 cents is don't be dumb like me. Make it as big as possible. It's always a question of fancy vs function and that's ultimately up to you. But Last thing you want is not being able to find a Contractor or getting shoddy installs because they don't want to do the work in a tight space.
If you have to, pick some basic equipment and find their dimensions in the specs. Basics like tanked water heaters and big stupid furnaces tend to be bigger. Do a lay out with them and if you change it later, you'll still have space to work with. Some things like electrical panels and air handlers need 24" access in front by most codes, but as akos suggested 3 sided access, that's of course much better if possible.
The work table is going to be the driver. That suggests you might want to work around it. So, you've got the size of the table, and at least 3' in front of it to move around. More if you want to be able to set up anything in the middle of the room and work around it.
Plus, you've got lots of stuff in the room that doesn't like dust, and a work table suggests at least some dusty operations? you might want to rethink that.
After that, the size of the equipment is going to drive everything. As a general rule, you want 3' of clear work area in front of each piece of equipment, the full width of the equipment. Of course those areas naturally overlap if the equipment is located around corners, etc. If you're going to have storage in the room, keep it all away from the equipment as well. Most combustion equipment has clearance requirements on the label.
When I say work table I'm referring to laundry stuff along with one of those deep work sinks. The "work" table will be in the "work" shop. :)
Make sure to allow for any code required clearances. The electrical panel, for example, must have 3 feet of clearance in front of it, for the entire width of the panel, from the floor to the ceiling.
My biggest concern would be serviceability. Leave enough room to get in and work on everything in the space. Don't jam everything together. There WILL be service work required in the future, so you need to allow for that in the design stage to avoid major headaches doing maintenance work later.
Another thing to think about is make sure there is enough space to get anything in/out of the room with everything else already installed. One day you'll need to replace something like your water heater, and you need enough clearance to get the old one out and the new one in. Pay particular attention to any corners to be sure you can bring the equipment in/out using a hand truck without smashing into anything.
Bill
It looks like we've decided to have the laundry in the garage which will be divorced and connected by a breezeway.
Are you in an area where you won’t have freezing problems with your garage laundry room? That might be something to think about.
Bill
Dirty laundry in divorced garage? Hmmm.
Having a separate garage is a good idea for a variety of reasons, imo, and I'm glad you're thinking seriously about the mechanical room requirements in the design phase.
I do have a question about laundry in the garage. Whenever I leave a shirt or towel in the garage, it ends up smelling like whatever is stored in the garage, including vehicles, lawnmowers, gardening supplies, and whatever stuck to my bicycle tires. Also, in my dream design, the laundry room is separated from the master bedroom by a walk-through closet. I want to minimize the distance that we have to carry laundry. This gets more important as we get older.
One thing that I miss in our current laundry room is a utility sink. If you have space, I would consider adding one if you haven't already. Honestly, I didn't even think about it when we bought the place, I must have just assumed every proper laundry room has a sink. If you end up with the laundry in the garage, definitely put in a decent sink.
Does your master bedroom include a walk-in closet, and is there any chance you could squeeze a washer/dryer in there? It makes a lot of sense to have the laundry done in the master closet for a home that you are retiring in. Noise is not a problem with modern machines: they are quiet enough that they'll be fine so long as there is a proper door to close, and maybe some fiberglass batts in the walls. Even if you have to shrink the bedroom a little bit, I think it is worthwhile.
Some also put washing machines in the master bath. It works fine, I'm just not as big of a fan. Still better than a garage though.
5/8" drywall is a big help for noise reduction too. I like to use 5/8" everywhere, but if you have a noisy place like a laundry room, using 5/8" at least for that one room will help to limit how much you hear the machines in adjacent spaces.
Bill
I would 2nd this idea.
I have my washer/drywer in the bathroom right by the walk through closet to the bedroom, works great. Very convenient, no need to carry laundry from one side of the house to the other. No issues with noise.
The only change I would do is to design in space for a drying rack.
What about a network/data cabinet in the mechanical room?
One of the best reno upgrades we did was to move the laundry close to the bedroom/bathroom.
I use CAD now but we use to draw the rooms on paper and use paper cutouts that represented the size of the items we needed to fit in a room.
If you have the ceiling height the ERV may not be an issue.
For a typical house, you're better off with a wall-mounted network setup since it will take less space. A typical full rack is about 2 x 3-4 feet in footprint and you need another 3 feet of clearance for each door. When I lay out datacenter floors, I allow a 4 foot front isle and a 3 foot rear isle, with a 4 foot (usually more like 42") space blocked out for racks. We run rows like this about 20-3o feet long (10-15 racks), with the fronts of two rows facing each other, so every other row faces the opposite direction. This allows design with blocks of about 30 racks. I've done facilities up to a bit over 700,000 square feet laid out like this.
For a home, you typically have something less than 48 network drops. There are several ways to accomodate this, a 48 port rack mount patch panel, two 24 port panels, or four 12 port wall-mount "66 block" style panels. I prefer 24 port patch panels (easier to add a drop or two as needed) in a wall-mount "rack" about 4" deep. I use small closet shelving to hold up things like network switches and cable modems.
If you want to go with a "real" 19 inch rack, I'd use a small swing-out open frame rack of maybe 10-15U (1U is 1.75" of vertical space). This should be enough space for most home networks, but still compact enough to not eat up too much space. Be sure to provide a dedicated electric circuit, not so much for capacity, but reliability -- you don't want a vacuum cleaner to trip the breaker and take your network down, for example.
Bill
In my current house we have a large Legrand On-Q enclosure with hinged door and I plan on using the same thing in our new build. The fit between studs, come in various size and some allow you to install a receptacle inside for your route and modem.
https://www.legrand.ca/audiovisual/racks-and-enclosures/commercial-racks-and-enclosures/28-hinged-door/p/en2860
Arnold
Hey Bill,
Depends on the size of the house and the scope, of course. And this is definately your wheelhouse. but I question if racks and patch panels are a bit much for this application? Especially when trying to fit in tight spots less equipment helps.
What about just neatly ziptying the drops and have them come into a freestanding switch?
I did a POE system that way, powering a few ceiling mounted AP and speakers. Realized I didn't need a rack and patch panel when I could terminate the at cat6 cables right into the switch.
I would always use a patch panel. Patch panels are much easier to terminate than RJ45 plugs, and they keep the cabling from moving around when you change things. The solid wire type of cable that is intended for installation in buildings isn't intended to be flexed frequently, that was patch cords use stranded wire instead. The tradeoff is stranded wire has slightly higher loss per unit length (not data loss, signal strength loss).
The patch panels that mount in 66 block frames are a good fit for smaller installations that need to be compact. These patch panels usually give you 12 ports in about 2" x 10" or so, and maybe 2" deep. They're great for residential systems up to maybe 24 drops (using two panels). If you need more than 24 drops they're still an option, but at that point "regular" patch panels intended for 19" rack mounting start getting more space efficient, you just need to add a mounting bracket to mount them to a wall.
Most people using a full rack at home (and I'm not one of them), are tech hobbiests. They'll put some servers in there too. Racks are a great way to organize things, but they're big, and they're very expensive for what they are when purchased new. You can almost always get them used for really cheap or even free, but you have to find them locally otherwise freight costs make them too expensive again.
Bill
Mechanical room to me means WH, HVAC and electrical etc.. Washer and dryer not in that list (for me).
My current design, which is approximately 1,900 ft-sq, has a mechanical room that's 8' x 7'. I have a WH, ERV, space for potable water plumbing distribution and an electrical panel. This room is located on an external wall. On the outer wall is where my electrical service will feed to/from. ERV vents go right up and out that same wall. I'll be running ducting, electrical and plumbing lines up in a chase (as trunk line, then feed out laterally for branching).
I have a separate laundry room spec'd, which is 8' x 9'. Non-stacked washer and dryer and a utility sink. Plumbing goes into an interior wall (adjacent to the mechanical room). Dryer up against outside wall for side venting. Small window. Room for a folding table and some shelving.
I specifically sought to split things up because I don't want to be tripping over laundry when I need to service equipment!
Watch out for room ventilation requirements for water heaters. Manufacturers seem to want ventilation for rooms less than 70 ft-sq.