Gym with no windows/ long ramble

HI there, I'm a heating and plumbing engineer by trade and so I do come across a few ventilation systems- mostly the domestic variety fan in bathrooms.
However, a regular cust - who runs a gym, is having problems with the sweaty lot in the gym. I'm guessing they've also increased their numbers over the last year and with it being summer in London- it's hot humid add that to the heavy breathing and showering. It's not regular gym with classes as we know it. These peeps train short and hard, heavy weights and lots of jumping for half an hour then most of them run home! I know!!
Anyway, the point is there are remnants of what I think was a ventilation system. Two big 500mm ducts terminating in an internal well of the building- where the fire escape is.

One terminal looks like it's got a fan in it and has power cable to it. The other looks like it's got a square box with door- maybe a filter? This is hard to describe.. SO I'm calling the one the F- with fan outside the building and the other B box for filter.
Inside F run's a couple of foot and then has two ports for smaller ducting- and I'll get to that in a moment.
B also runs into twp ports but ends in another ?FAN more than a few meters away.
Neither of them work I'm told or if powered up very noisy.

The other thing is the tiler that installed the 6 showers has also added to this, yup you've guessed.
He has added an extractor fan that allows 3 extractors to connect via a joining box, on to one port on F- and the wc extractor on the other port.
On B he has joined the remainder of the showers via various means of soft white ducting tube and loads of gaffer tape.

Needles to say apart from purring noise there's little or no effect- that I can tell.

NOTE- that they also have two air- coolers/ air con units, but to me they not as effective as they could be- apparently they are working as they should = they get annual checks., in the workout area- separated by swing shut doors.
NOTE- They also have am open flue boiler for hot water- 26KW that needs it's own passive ventilation. Boxed in but take the air from above the ceiling.

FINALLY MY QUESTION- Can I refigure the extractor fans using these large diameter- 500mm? with perhaps rigid ducting and one duct the B one as air supply and the F one incorporate a large fan. Or use the one that's there- I'll go back to test.
The room doesn't have windows and these ducts are all above the bathroom/change room area in ceiling void.
I would like 'fresh' to vent into the workout area as well as the shower/change room.
Best question is how do I find out about this? I'm keen to expand my knowledge- any design books recommended/ courses?
I just don't know who to ask and look forward to any responses- if you've not tuned out by now.
Thanks for reading


  • Edi
    In the first instance I would do the checks to see if the fans are actually working, if they are send a message with the fan details. You have a number of issues, issue one is the summer effect where for a few weeks in a year any indoor environment becomes uncomfortable unless you have adequate Air Conditioning, issue two if the Air Con isn't sized for UK extreme weather conditions you may not have enough cooling capacity available, and issue 3 is how much air should we extract because without extra cooling you'll be extracting the Air Coned cool air and replacing it with outside ambient air which could be 30C plus and no matter how much air you move you can't reduce the inside temperature below the outside ambient without added cooling. The first question you should ask is what do they actually want the gym environment to be. Chilled air which would mean increase the Air Con and perhaps add a low level of extract and supply to keep the oxygen levels comfortable. Feel a breeze over your skin with lots of added Oxygen which would mean turn the Air Con off and rack up the ventilation rate, or a combination of the 2 which would be the most expensive to run.
    If it was me I would buy 5 or 6 cheap pedestal mounted fans and let the guys working out feel a breeze over their skin this would create a cooling effect on its own and cost very little

Sign In or Register to comment.