# What size roof vent do i need ????



## spire2003 (Dec 21, 2008)

I have a 1998 Elddis Autostratus EK. The front overcab rooflight leaks after heavy rain. Now this may sound daft, but if the van is facing uphill i have no problem. If it is facing downhill i do. The rooflight is in a recess & i think water must gather there when the van is facing downhill. Sometimes there is no problem until i drive off & then i get a cold shower. Does anyone think this is a permanently open vent ( if that makes sense) & the swishing of the water on movement makes it enter the vehicle. Even when it is fully shut i always think there is air coming from the vent. My final & most important question is how do i know from the inside the size of the vent as i would like to replace it. Do i just measure the inside frame? If so this is just under 425 x 425 mm. Anyone near Chesterfield had one changed recently ? How much & by who ?? Any advice appreciated.


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## 747 (Oct 2, 2009)

Hi spire,

There is a chance that the leak is due to failure of the waterproof joint and it just needs re-seating with fresh mastic.

Before you do anything though, check the condition of the rubber seal between the frame and the clear plastic window. If it is perished, that might be the cause of the leak.

I, and probably a few others, have taken out the rooflight for nothing, as the fault was elsewhere.


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## spire2003 (Dec 21, 2008)

Hi 747

Can what you suggest be done from the inside by removing the screws that are on the inside frame ???


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## 747 (Oct 2, 2009)

Hi spire,

As far as I know, all rooflights are screwed together from the inside.

You normally remove all of the screws. In my case the inner frame stayed in place but I do not know if yours will.

You need a couple of thin steel wedges to ease under the outer frame and very gently break the existing seal on the outside. Be careful with the paintwork.

Clean up both surfaces to get rid of the old mastic. I used white spirit and plenty of rags. The new mastic can be bought either in a tube, so you need a sealant gun, or in a roll (of various widths and thickness).

Once the surfaces are clean, refit, with new mastic applied, and screw the bits together again.

Hope that helps.


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## trevorf (May 16, 2005)

As said, no need to replace if there is nothing wrong with it.

Undo screws on the inside of the frame, get onto roof and run a stanley knife blade under the old mastic, lift out entire roof vent, clean off old mastic and re fit using sikaflex 512. 



Trevor


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