Cat Flaps and Double Glazing?

Welease

I need to put a cat flap on an external double glazed door (through the glass).. On reading the instructions, it said for double glazing it would need to installed at the factory, which is obviously not an option..

Is there any particular reason for this? Apart from the extra hassle of having to cut the 2 panes (in exactly the same place).. is there a reason why I shouldn't attempt this myself?

Zimmerframe

Welease wrote: »

I need to put a cat flap on an external double glazed door (through the glass).. On reading the instructions, it said for double glazing it would need to installed at the factory, which is obviously not an option..

Is there any particular reason for this? Apart from the extra hassle of having to cut the 2 panes (in exactly the same place).. is there a reason why I shouldn't attempt this myself?

Methinks there is a gas or vacuum between the two panes, which obviously won't be there when you cut them.

Welease

Zimmerframe wrote: »

Methinks there is a gas or vacuum between the two panes, which obviously won't be there when you cut them.

Thats what I was thinking.. I suppose my question is.. Is the removal of the vacuum (or gas) just going to lower the insulation efficiency of the double glazing (which is expected and is ok), or would the removal cause potential structural issues.. ie it could collapse (which is obviously not ok)..?

Welease

Bugger.. found some more info.. seems like the double glazing uses toughened glass, so it will crack rather than be cut..

There are a few companies that can get it installed, but the cost is likely to be around €300+..

Plan B then.. see if I can go through the cavity wall

BryanF

Welease wrote: »

I need to put a cat flap on an external double glazed door (through the glass).. On reading the instructions, it said for double glazing it would need to installed at the factory, which is obviously not an option..

Is there any particular reason for this? Apart from the extra hassle of having to cut the 2 panes (in exactly the same place).. is there a reason why I shouldn't attempt this myself?

its a Cat, pick the smallest window opening section and modify that

TskTsk

Welease wrote: »

Bugger.. found some more info.. seems like the double glazing uses toughened glass, so it will crack rather than be cut..

There are a few companies that can get it installed, but the cost is likely to be around €300+..

Plan B then.. see if I can go through the cavity wall

I enquired about the same thing a few months ago and was given a rough quote of €400-€450 quid.

the_syco

BryanF wrote: »

its a Cat, pick the smallest window opening section and modify that

Agreed. Also, came across this wacky invention: http://www.catflaps.com/contents/en-uk/d141_microchip_catflap.html

massy086

if you are in dublin send me a pm im a dublin based glazing company .the price,s you are getting quoted seem crazy

Welease

BryanF wrote: »

its a Cat, pick the smallest window opening section and modify that

??? Not sure what you mean

How do you modify the glass, if the glass can't be modified because it toughened.. Unfortunately the windows are all large.. the smallest window section available being about 6ft x 3ft..

Welease

the_syco wrote: »

Agreed. Also, came across this wacky invention: http://www.catflaps.com/contents/en-uk/d141_microchip_catflap.html

We have something similar to that without the chip detection.. But it would still have the same issue, as it is apparently impossible (or extremely difficult) to install at home because of the toughened glass in double glazing.

The easier route now seems to be buying a replacement rear door with only a glass panel in the top half..

martinn123

Welease wrote: »

We have something similar to that without the chip detection.. But it would still have the same issue, as it is apparently impossible (or extremely difficult) to install at home because of the toughened glass in double glazing.

The easier route now seems to be buying a replacement rear door with only a glass panel in the top half..

No, just replace the glass with a flat PVC panel, you will need the height, width, and thickness, is the door 1/2 and 1/2 in which case only replace the bottom half.

You can then cut the pvc panel, using the template which will come in the box with the cat flap..

If the door is all glass, you can get a panel which has a glass section at the top and pvc at the bottom.

Ring your nearest window fabricator, they will do this for you easily.

heinbloed

Glas panes up to 1.4 meters from floor level have to be made from safety glass(building regulations).
This safety glass can't be cut.
So the prozess of producing a double pane safety glass unit with a cut-out is complicated, the glass panes being cut to size and then heated (to produce the safety-glass effect) will expand and shrink .....
Because of an uneven distribution of the material (the glass) the expanding and shrinking will lead to an increased risk of material damage.

Therefore the high price.

Welease

martinn123 wrote: »

No, just replace the glass with a flat PVC panel, you will need the height, width, and thickness, is the door 1/2 and 1/2 in which case only replace the bottom half.

You can then cut the pvc panel, using the template which will come in the box with the cat flap..

If the door is all glass, you can get a panel which has a glass section at the top and pvc at the bottom.

Ring your nearest window fabricator, they will do this for you easily.

Ahh gotcha.. Its a wooden rimmed door with the centre piece (90% of the door) being double glazed.. I could as you suggest remove the glass, add a wooden panel and glass the top half.. but I'm thinking it would likely be similar cost to getting a new standard door from a builder merchant and cutting in the flap myself.. Definately something to consider once I get an idea of all the potential costs..

Unfortunately the missus won't go with my plan.. no cats

creedp

Welease wrote: »

Ahh gotcha.. Its a wooden rimmed door with the centre piece (90% of the door) being double glazed.. I could as you suggest remove the glass, add a wooden panel and glass the top half.. but I'm thinking it would likely be similar cost to getting a new standard door from a builder merchant and cutting in the flap myself.. Definately something to consider once I get an idea of all the potential costs..

Unfortunately the missus won't go with my plan.. no cats

That's one important/expensive cat. Luckily you won't have to get a new airtightness test and BER done:) Personally I would go with Option B: No Cat .. or else install a cat knocker on lower half of door:D

CamillaRhodes

Sorry to re-open an old thread, but I need to get this done (by someone, not myself!) and have been quoted €300-350 (for a whole new unit with the catflap cut into it). Does anyone have any suggestions for anyone who could better this price?