Banquet Room Sizing

[bcrum51]

Ok this is my first "commercial" job its new construction. One of those friends that we all have when they need a job done called me today...
He is adding a new addition to his restaurant its approximately 3000sq ft 9ft ceilings average insulation wide open floor plan going to be used as a banquet space that will hold approximately 150-200 people which is probably over shooting the capacity. Im going to look at the building tomorrow and see if im up to doing the job. He is a cheap skate which is probably why he called me to hopefully get a "good deal". Basically based on the info above can any of you give me some tips on sizing this space before i go check it out. He wants a split system seems like my rough calculations are coming up somewhere within 60k and 70k btu's I maybe way off on this but thats why im here to see what someone more seasoned has to say about it. I just need some rough idea so i can give him a price range to expect.

[bowhunter86]

Seems close without actually doing any math. One thing i would recomend is staging or some type of load control. Spaces like this are always problematic if the unit isnt sized right. You need enough capacity to cool the space when its loaded with people but you dont want to bang on and off when theyre only using it for small groups. You may be better off going with 2 splits one on each side with there own stats if you wanna stay cheap. Ive seen that quite often in spaces like this. Lots of chapels and santuarys are done that way.

[bcrum51]

thats what i was thinking 2 splits on each end of the building 2 3 ton units any idea of heating btu's i was think 100k total out btu so 2 60k 95% furnaces???

[ACFIXR]

I did a banquet meeting room last year that had 3700 sq ft with 9' ceilings. The PE had put 4- 5 ton package heat pumps on with a total of 2000 cfm of outside air.

[bcrum51]

What was your total occupancy ??

[ACFIXR]

What was your total occupancy ??

Sorry, but I can't find that info.

[bcrum51]

thanks anyway appreciate the help still on the fence about even doing it

[dlove]

thanks anyway appreciate the help still on the fence about even doing it

well the Rule of thumb method is taboo around here But, 2 to 2.5 cfm per sqft. and would lean towards the 2.5

and yes you will need OA. 9' ceilings is not that high when you have most people standing and dancing.

If you don't move the air, people will get hot. If this guy is cheap he better hang on, and don't forget the smoke duct detectors. He will need a permit and drawings. I wouldn't waste to much time with out bidding the drawings. but if you give a quote make sure your happy with it. Any owner builder i work with will hound you if there are any surprises. But ACFIXR has a good drawing there.

RTUs my be his best bet, save cost on piping and electrical. use plenum return.

[bcrum51]

well the Rule of thumb method is taboo around here But, 2 to 2.5 cfm per sqft. and would lean towards the 2.5

and yes you will need OA. 9' ceilings is not that high when you have most people standing and dancing.

If you don't move the air, people will get hot. If this guy is cheap he better hang on, and don't forget the smoke duct detectors. He will need a permit and drawings. I wouldn't waste to much time. But ACFIXR has a good drawing there.

RTUs my be his best bet, save cost on piping and electrical. use plenum return.

I think you hit it right on the head

[ottawaair]

Around here, that would have to be engineered and stamped to even get a permit. With that occopancy load, you will need a lot of fresh air. Then the correct amount of heat/cooling to overcome the fresh air load alone. Air change and cooling will be the major factors. I would drop it off to an engineer before I even considered giving a price.

[joebear]

i think you need 10 tons, 1 ton per 20 people,200 people 10 tons

[hcong]

I attached a rule of thumb check: http://hvac-talk.com/vbb/showthread....1098071&page=2

Restaurants:
Cooling: 48 BTUH/SF
Heating: 3.0 BTUH/SF

Every person will need:

15 CFM of Outside Air
280 BTUH Sensible Heat Emitted
270 BTUH Latent Heat Emitted

Just people alone you are looking at 9.5 tons without taking into account your building construction.

I would use Manual J or do a quick load calc.

[dlove]

I attached a rule of thumb check: http://hvac-talk.com/vbb/showthread....1098071&page=2

Restaurants:
Cooling: 48 BTUH/SF
Heating: 3.0 BTUH/SF

Every person will need:

15 CFM of Outside Air
280 BTUH Sensible Heat Emitted
270 BTUH Latent Heat Emitted

Just people alone you are looking at 9.5 tons without taking into account your building construction.

I would use Manual J or do a quick load calc.

that's about 1.3 cfm per sqft. and it may work. My feeling is your on the boarder line. and when your paying big bucks to host an event. i don't want to hear "Captain the AC is doing all it can" when im hot. :gah

but taken into account you didn't included the structure so the rest remains to be seen. I built out many conference rooms and 2 cfm per sqft is what has been consistent and has worked for me.. because this is a new add on and not existing, If this owner is smart he should have the architect and ME, design a cost saving structure. otherwise your spinning your wheels