Keeping the workshop cool

[Jon LawesParticipant @jonlawes51698]

Working shifts I'm finding time in the workshop is precious, and right now the only time available is in the afternoon after my workshop has been heat-soaking in the sun all day. It's a high tile-roofed single garage in a block of other garages. No door other than the main one. The rear wall faces out onto a domestic garden so I can't easily put ventilation in.

Does anyone have any tips for reducing the temperature in there please? It's unusable at the moment as its routinely hitting 35 degrees, and even with fans trying to drag the air out its really not helping much.

I know this weather is due to break soon but its a recurring problem whenver it gets a bit warm. I'd be interested in how the model engineers in hotter climates than the UK cope (other than being made of sterner stuff than I).

Thank you,

Jon.

[Jon LawesParticipant @jonlawes51698]

[JAParticipant @ja]

I have no idea on this one. My workshop is reaching 30 degrees before lunch, before the sun is shining on the workbench.

I have started getting up in the early morning to avoid the heat. However I have effectively been evicated from the workshop. In a way I have settled into a cold winter work style, doing all those important jobs usually put aside so that I can mess about in the workshop.

JA

[Rik ShawParticipant @rikshaw]

Jon – My situation is different in that I have both doors and windows open and a fan blowing. Even so, a short half hour session after noon in this weather is as much as I can take. A free standing portable AC unit might sort your problem as it would mine but unfortunately my workshop is so rammed full that there is no room for anything like the size of unit I'd need.

Rik

[Dave HalfordParticipant @davehalford22513]

Jon,

Fans are better at blowing than sucking, least ways my leaf blower very obviously is, so if the fan isn't in a wall or door it pulls air from the sides. Try blowing air into the workshop.

I'm assuming you already have roof insulation 

Edited By Dave Halford on 22/07/2021 10:55:36

[vic neweyParticipant @vicnewey60017]

My leanto workshop has a transparent roof! I have shade netting and old camouflage netting strung across but it obviously gets rather hot. It even melted some hot melt glue sticks a few years back

[David NobleParticipant @davidnoble71990]

It seems that I'm more fortunate than most as my workshop is in the cellar of the house. Even so, it's hitting 20c in the afternoon.

David

[Ady1Participant @ady1]

I use the spanish system

Up at 5am until about 1pm

have lunch and a siesta until about 3.30 and then can keep going until 11pm ish

 

The USA only keeps going in the heat by using gigawatts of airconditioning

Edited By Ady1 on 22/07/2021 11:19:35

[Dave HalfordParticipant @davehalford22513]

Posted by vic newey on 22/07/2021 11:02:25:

My leanto workshop has a transparent roof! I have shade netting and old camouflage netting strung across but it obviously gets rather hot. It even melted some hot melt glue sticks a few years back

Anyone remember the old series 2 Landy had a tropical roof option, basically a 2nd roof with something like a 1/2" air gap between them.

[Jon LawesParticipant @jonlawes51698]

I don't have any loft insulation; the peaked roof is very tall but I would have to put in a ceiling to insulate it, or I suppose insulate under the tiles directly. I guess the advantages would be year round if I did.

During the colder weather I seriously thought about putting a fan and ducting to take the hot air from the peak down to the floor level; any hot air you introduce into that space with a heater soon disappears vertically!

[Graham MeekParticipant @grahammeek88282]

My workshop has a corrugated asbestos roof, beneath this a layer of roofing felt which is on 19 mm water proof chipboard. Beneath that is 25 mm of foam insulation with foil on both sides. A skylight in the centre lets in natural light and the Suns rays. The skylight has two layers of twin wall plastic separated with a 150 mm air gap.

Cosy in winter, but useless now. 33C last night at 9.30pm. The main window faces due West and I regularly see the Sun set over the Brecon Beacons, so the rays are with me all day. Currently the workshop is a no-go area.

With 37% of the Earths energy consumption set to be used on Aircon by 2050, it is a problem worth some serious consideration, if the figures are to be believed. For my part I have often thought the Rev Stirling's engine holds the key here, but it needs someone better than I to sort it out.

Regards

Gray,

[Andrew TinsleyParticipant @andrewtinsley63637]

My garage is integral to the house, double glazed and cavity wall well insulated, as is the floor between garage and first floor of the house. To top it all the sectioned garage door is well insulated too. I didn't really want to spend all the extra cash during the build, but now I am very glad that I did so. It is delightfully cool in this heatwave and requires only a couple of small radiators ticking over in the depths of winter to make it cosy.

Andrew.

[not done it yetParticipant @notdoneityet]

100mm insulation and pretty well air-tight lets me work, even in the afternoon. Leaving the door open for long periods, when all the workshop contents will warm up to ambient is not good – it can take days to cool down!

A small portable air-con unit would make a difference – as long as you are not attempting to cool the surrounding area.

Changing hot air for nearly-as-hot air is not really a viable plan.

[CalumParticipant @calumgalleitch87969]

You might consider those ice-cooler machines from on Amazon – if you search for air conditioning and look at the ones that are far to cheap to believe, most of them work by cooling air in melting ice, and you can usually acquire sacks of ice from a supermarket for a pound or two. Probably the cheapest solution for a few days a year; if you're overheated all summer then a proper AC unit would be the way to go. I wonder if you could get one from a scrapped vehicle? Those are designed to cool smallish spaces, but with much more heat input, so might be quite efficient.

[not done it yetParticipant @notdoneityet]

I ‘ve just been in my workshop this last half hour. 21 Celsius on entry, still the same as I came out. Back in, in about 10 minutes. I’m re-fitting a set of pistons in an engine block, among other minor bits and pieces that need attention.

Relatively cool in there, compared to out in the sunshine (and in the house as well).🙂

Still at 22 degrees @15:15.  Probably a good jobbI’m not running machinery, mind.

Edited By not done it yet on 22/07/2021 15:19:26

[DalboyParticipant @dalboy]

At the moment the present workshop is unbearable since we had a large conifer tree removed before that I was able to work in there in reasonable comfort until mid afternoon when the sun shifted.

Hopefully when the new workshop is up and running I will find a air con or something similar to help make it comfortable to work in.

In the house we have a fan unit that you fill with water and a felt type belt dips into the tank of water and then rotates up into the path of the fans air supply this cools the air before expelling it into the room. It also has a tray which ice can be placed and this drips onto the felt pad. It is a Goldair unit not sure where from as I paid a small sum of £5 at a bootfair many years ago best £5 I spent in heat like this

[DMBParticipant @dmb]

Many, many years ago, I was in a state run school, taken over from the private sector and previously was a large country house. At some stage, an indoor swimming pool was added on with apex glass roof. So far, so good. The county council altered the swimming pool to another use. Guess what? A woodwork room! My god did it get hot and trying to shove a jackplane in there, phew! Eventually it became a classroom with desks and chairs. A new annex was built with a metalwork room one end and a woodwork room at the other separated by a coke fired boiler house in the middle for winter warmth. Much better after that awful swimming pool cum woodwork room. Those were the days, hammering hot metal from the forge and singing along to a transistor radio blaring "House of the rising sun" by The Animals.

[DMBParticipant @dmb]

Early this week, up very early by birdlife and bathroom beckoning, so quick bite to eat and out to nice cool workshop. Around 10am, thought it was a little warm so looked at thermometer; 90°! Called it a day, back indoors for remainder of breakfast and do other jobs in house, where it was cooler for a time. Even the cat sleeps under the ceiling fan in the afternoon. Who'd have a fur coat this weather?

[Speedy Builder5Participant @speedybuilder5]

problem with the small portable air con units is that they pump out the hot air, which is replaced by the hot air drawn back into the room. They dry the air as they cool it which can be an advantage.

[john halfpennyParticipant @johnhalfpenny52803]

Going back to the op problem, I would create a through draft by putting some kind of opening opposite the door – opening to be closable of course. Openings on opposite walls usually create a reasonable air flow, though it might be from the sunny to the shady side. Flow might be fan assisted, maybe with the door 80% closed.

[Dave HalfordParticipant @davehalford22513]

The op's problem is his back wall 'opens' onto someone's garden and the workshop is part of a garage block, so options are limited.

[Martin KyteParticipant @martinkyte99762]

Ground source heat pump working in reverse.

Build a foundry. Do an hour in the foundry and then retire into the cooler workshop.

Put a night shift on.

Go fully CNC and operate remotely from the house.

Buy an old church and move the workshop there.

Sit in the garden and eat ice cream untill the weather cools down.

Seriously I do sympathise. If only we could store the heat of the summer to warm us up in the winter.

The best idea I have heard of is plastic beads filled with wax. You create a matrix of the beads and plaster. The wax melts at around 22 C absorbing heat from the room and delaying the temperature rise. On cooling the room 'hangs' at the freeze temperature as heat is given up by the wax. Essentially you use the phase change to buffer the temperature rise in the room.

regards Martin

[BazyleParticipant @bazyle]

Nowhere in the UK is above 20C all day so there is cool time at night. As with your house you need insulation and thermal mass which you cool down at night and seal it up in the day to keep the heat out. You can also paint the roof white, spray it with a mist of water, shade the walls and windows with a lightweight frame projecting from the roofline a couple of feet covered by cardboard or sheeting that can be removed in winter to let the meagre sun provide warmth.

[Jon LawesParticipant @jonlawes51698]

Martin, the wax beads idea, although probably not for me, is very intriguing and has given me something to follow up on for interests sake at least, thank you.

As I suspected, my options are fairly limited. I may have to just wait this out for the moment. Thanks for all those who were able to give some ideas, there was certainly a lot of food for thought.

[Martin KyteParticipant @martinkyte99762]

Google Phase Change Heat storage or some such.

regards Martin

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