I'm fitting a maxx air fan today....screws or ct1 is the question

[Ads86]

Hello all

I'm using the rear sky light which is a prefect fit to just slide the max fan into. I'm then running a 12v connection straight from the fuse board in the garage.

Ive got some sikaflex for the maxx fan to sit on along with the screws that came with the unit. I'm always nervous about creating holes in the roof so I'm debating to just use ct1 to glue the new fan in and not using any screws at all.

It's strong as hell, waterproof and flexible. The only downside I can see is if I come to take the fan surround out and it's stuck on the roof. But I doubt I'd ever got back to a normal hatch so I'm not really worried about that.

Any thoughts? Or has anybody already done this with ct1?

Cheers

 

[oozzie]

Not done this myself but how was the old skylight held in? I’ve got a remis vista on mine which has a few cracks so got a heki to put in but don’t think the screw holes match up so will possibly be looking at the same as you. If the ct1 is that strong you might be ok.
Oozzie

 

[Roby2008]

I replaced a heki with a maxxfan, hole was the same size, screw holes for the maxxfan were different but scewed in anyway, plenty of Sika and all is well.

 

[Ads86]

I've gone with the ct1 approach. I really didn't want to put holes in the roof. My old roof vent seemed to clamp on from the interior surround.

I'll see how it goes, it's only been on a couple of hours and it feels solid already. They say it can withstand +120°c and -40°c.

 

[Raul]

If you are too worried, you can get an adapter for max fan, van and location specific. That way no worry about the screw holes.

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[Howard B]

I used both.

 

[delia]

I have fitted 2 Maxfans. On the last van used screws as per instructions but thought it was a bit of a messy bodge covering them. But it stayed on and didn't leak. On this van I took out the existing fan and fitted the Maxfan using sikaflex only, no screws. So far after 22k miles it has stayed on without leaks.

 

[fishplug]

I have fitted 2 Maxfans. On the last van used screws as per instructions but thought it was a bit of a messy bodge covering them. But it stayed on and didn't leak. On this van I took out the existing fan and fitted the Maxfan using sikaflex only, no screws. So far after 22k miles it has stayed on without leaks.

This mirrors my experience. Haven't done 22k in the new one yet, but it's done somwhere around 10k without issue.

As I understand it the new MaxxAir fans are shipped with a cowel that has dimples which you can drill if you want to screw it down but they've pretty much acknowledged that there's a wide enough area to put more than enough bonding to secure it without screws.

The only thing I would say is that I still put a wooden frame on the inside which both adds a bit of structure and rigidity to where you've just cut a big hole, but also gives you something to clamp against while your CT1 / Sikaflex / bonding agent of choice is curing.

A nice squeeze will ensure there's no chance of a leak. Lots of small clamps will give more even pressure than just four big ones. Think I used one big one per side and two more smaller ones. Might have been overkill, but I tend to over engineer stuff.

 

[ivorantony]

Yes I used both as well,

 

[Ads86]

The ct1 seems to be holding up so far.

I do have a nasty draft coming in when the fan is closed. Going to get on the roof this week and check the plastic cover is attached properly

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[ivorantony]

You probably need the additional rubber seal, that’s a extra because it’s required to have positive ventilation even with the hood shut,

 

[Ads86]

You probably need the additional rubber seal, that’s a extra because it’s required to have positive ventilation even with the hood shut,

Ah I see. That would explain it. I've already got a roof vent above the kitchen that vents the van without a rubber seal.

This would be awful in winter!

 

[Just smiffy]

The ct1 seems to be holding up so far.

I do have a nasty draft coming in when the fan is closed. Going to get on the roof this week and check the plastic cover is attached properly

You can get a full seal of eBay, just search Maxx fan seal and loads come up and a few £’s…

 

[Johnen]

The screwholes on my maxfan were the source of the only water leak I have ever had. Have to say that the maxfan is the best addition ever fitted!

 

[Vaman]

Sikaflex, screws and allow for the mastic underneath, not all squeezed out. I put tile spacers underneath. Then fitted the extra canopy gaskit kit. I have found during this trip that the canopy can stick to the extra gasket (despite the fact I got the official extra gaskit kit). The worry is the motor/gears may get damaged due to the extra loading. Will apply french chalk or a thin film of silicon grease when I get back on Tuesday (need an imperial allen, not available in French hypermarkets ).

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[lonnie]

Just sika for me. We've done many miles in the three years it's been up there with no issues whatsoever - including travelling with it up (not intentionally )