Rust-proofing the garage

CptKernow

Stuff seems to go rusty in my garage. It is a 1950s single skin breeze block construction with a pitch roof.

I was thinking of insulating the roof with some celotex boards as a start. And maybe putting a small oil heater or something in there.

Is this a good plan?

paul_the_pedaller

If you can get some ventilation in there that will help, preferably on opposing sides to help reduce what will more than likely be condensation this time of year. Single skin will never truly be waterproof unless it's properly rendered. If you can get an electric greenhouse heater in there that'll be safer than an oil heater but probably won't be a total cure.

pinno

You don't have to heat the thing up. In fact, heating it can be both expensive and some types of heating may produce water as a by product like gas or oil.
All oxidisation requires oxygen, salt and water for it to occur. Salts occur naturally in the environment. If you take one of these out of the equation, you stop oxidisation. It's impossible to completely avoid any possible rust but you can reduce it to a minimum.

Then you need to consider this:
Has it got a roll/swing door? Does it (they) seal against the elements? What is the door into the garage like? i'e wood/uPVC etc. Has the garage got a window - does is seal? Is it double glazed? Isit an old wood window frame? Has the breeze block got a damp proof membrane? Again, is there rising moisture?
If there is a big metal roll/swing front door, can you get rid of it and brick it up leaving space for a wide entrance door that is practical and in the process, get rid of the original entrance so that you have say 1 window and 1 door? Replacing a roll/swing door with a 'proper' one can be pricey.

Line the whole thing with Celotex/Kingspan. 30mm is probably sufficient but 50mm is far better and can turn the garage into a really comfortable 'working' environment. You can then go the whole hog and plasterboard plaster it or more cheaply, line it with sheathing ply - 10mm will do. Build a wooden frame throughout to accommodate the insulation board and whatever you propose to cover it with.
The best thing, providing that you can seal it off, is deploy a de-humidifier.

ugo.santalucia

Pinno wrote:

All oxidisation requires oxygen, salt and water for it to occur. .

Oxidation...

oh dear, here's my 5 year one lectures on redox reactions in the bin then...

I'd say water is almost compulsory, as dry oxygen is electronically a "triplet" and therefore not very reactive, despite its reduction potential being very high... salt, as you call it, is optional... some form of acid helps oxidation a lot... acid forms naturally in water, given we have CO2 in the air, as well as nitrogen and sulphur oxides, courtesy of diesel engines... acid itself is an oxidant

pinno

Quite correct Ugo, yes - oxidation but giving me a lecture doesn't cure the OP's problem.

ugo.santalucia

I think the solution is a good cleaning regime and very good lubrication. I don't believe in insulation. Highly insulated homes have more damp problems than less insulated homes, given equal temperature (and it will be equal in the absece of heating). Ventilation is more important.

pinno

ugo.santalucia wrote:

I think the solution is a good cleaning regime and very good lubrication. I don't believe in insulation. Highly insulated homes have more damp problems than less insulated homes, given equal temperature (and it will be equal in the absece of heating). Ventilation is more important.

In homes, humidity is produced by cooking, washing, breathing! etc. This is a garage. You're not going to do that in a garage. It's an erroneous comparison.
The OP's garage has too much ventilation if you like. Increasing it is only going to make it worse. There maybe sources of damp as I have outlined from windows and doors. If it is inherently damp due to it's construction, then it is a problem.
In my house, we cook, wash, breathe (honest) and we also have a dehumidifier. At this time of year when we're doing the laundry for ourselves, 2 toots and the windows are shut most of the time, our dehumidifier is on from 7am to 7pm taking roughly 2 litres per day on a medium setting. The result is a very healthy environment. Without it, it would be opposite.
If the OP decides to line and insulate the garage, then he will need a small vent however, he will have sealed it off to most of the factors causing rust.

@Paul: Try and find a friendly builder who can give you some advice. I doubt it will be much different to what I am suggesting and simultaneously, you can avoid the pedantry that will occur here.

bernithebiker

Every house in France has to have a VMC; Ventilation Mecanique Controlé.

It's a large fan unit that sits in the loft and pulls air through the house via pipes and inlets in all bathrooms and kitchens (plus other rooms if you want). And rejects it through the roof.

It's the best thing the French ever did. It keeps a house healthy and 'breathing'. Nothing is worse for a damp, unhealthy atmosphere than a totally sealed house (as modern ones are).

The key to keeping a room dry is to ventilate it. Heating on it's own is very inefficient against damp. We have several holiday houses that are mostly empty in the winter, and the best way to keep them dry is to ventilate. The old Breton folk round here will throw open all doors and windows in the winter as soon as there's a decent breeze.

De-humidifiers are energy intensive and only work for small areas unless you buy really big ones.

Trying to heat a garage with an electric heater will cost you a small fortune. For about 1% of the running cost, install a ventilation fan.

sheffsimon

bernithebiker wrote:

Every house in France has to have a VMC; Ventilation Mecanique Controlé.

It's a large fan unit that sits in the loft and pulls air through the house via pipes and inlets in all bathrooms and kitchens (plus other rooms if you want).

It's the best thing the French ever did. It keeps a house healthy and 'breathing'. Nothing is worse for a damp, unhealthy atmosphere than a totally sealed house (as modern ones are). And rejects in through the roof.

The key to keeping a room dry is to ventilate it. Heating on it's own is very inefficient against damp. We have several holiday houses that are mostly empty in the winter, and the best way to keep them dry is to ventilate. The old Breton folk round here will throw open all doors and windows in the winter as soon as there's a decent breeze.

De-humidifiers are energy intensive and only work for small areas unless you buy really big ones.

Trying to heat a garage with an electric heater will cost you a small fortune. For about 1% of the running cost, install a ventilation fan.

A colleague has just installed one of these in his home in the UK. He was skeptical but said the results were great. No more dampness and condensation, almost straightaway. I think his was just a fan unit in the loft, no other ducting.

step83

Had to work on my own garage to stop it filling up with water, most of whats been said here is spot on.
Heating it is pointless youll just spend a fortune doing it. If the goal is to reduce the available moisture you need to find where its coming from. As Pinno said, damp course its a 50s single skin so good chance the damp course has breached somewhere.

Also look for anywhere the soil is showing through, remove and seal.

Walls, are they damp? if so you may have a breached damp course if it had one to start with. sealing the brickwork may help here. Also you may need to chase out and re mortar in places the damp has ingressed.

Leaks, are there any in the roof? Check for signs like salt marking on walls, discolouration etc loads online about it.

The entrance is an obvious ingress point the door likely doesn't seal well being a garage, also is there drainage in front? On mine the main issue was flooding due to driveway angle and poor drainage. I added a channel in front with a grate over which seems to have worked but as Pinno said if your not planning on putting a car in, put a door in to reduce the actual area.

VMC is a great idea, if you have a pitched roof you can mount it on the side with a shield a bit like the extractor fan unit for the hobs. If you have power it is ideal if not then louvered vents or a rotating vent if you can mount it to the roof would work. Long as you have a flow in otherwise youll have no air movement so the moisture will stay.

Not all the above may work or be relevant but its a start, youll never totally remove moisture partly because youll be n there breathing, but you can reduce the chance of rust but having airflow.

CptKernow

Thanks for the replies.

I wouldn't have thought ventilation was an issue as there is a roller door at one end, 3 single glazed windows and a not terribly tightly fitting door at the opposite end.

There aren't any visible signs of leaking, and there's never any condensation on the windows.

I suppose living near the sea and using the garage for turbo sessions could be contributing to the corrosive atmosphere...

The main issue isn't my bikes - I keep the good uns in the house. It is just stuff like tools and anything I store out there.

bernithebiker

CptKernow wrote:

Thanks for the replies.

I wouldn't have thought ventilation was an issue as there is a roller door at one end, 3 single glazed windows and a not terribly tightly fitting door at the opposite end.

There aren't any visible signs of leaking, and there's never any condensation on the windows.

I suppose living near the sea and using the garage for turbo sessions could be contributing to the corrosive atmosphere...

The main issue isn't my bikes - I keep the good uns in the house. It is just stuff like tools and anything I store out there.

Even though the door may be gappy, there's nothing to drive air through the garage. You may get the odd draught, but that's it. Nothing like an actual powered fan.

Having said that, metal stuff left in outside shelters is still going to corrode more than if left inside the house, especially if you have that Cornish salty air to deal with!

You can spray stuff with marine winterisation spray, basically a kind of thick WD40.

step83

I used to get tools rust a bit in my tool boxes, silica gel sachets solved it.