Today's top tip - cat flap.

[ProDave]

In anticipation of finally fitting the windows to our sun room, I fitted a "cat flap tunnel" through the wall.

 

I had ordered the cat flap but it had not arrived.  The quoted dimensions were 19.5cm high and 18.5 cm wide.  I had assumed * that was the overall size of the unit and the actual flap would be smaller.  I made the tunnel 18cm wide, constrained by being in between 2 studs.

 

The flap arrived today.  The actual flap is 18.5cm wide so of course won't open into an 18cm wide tunnel.

 

*Assume = An Ass or You and me.

[Thorfun]

  On 16/04/2021 at 12:39, ProDave said:

In anticipation of finally fitting the windows to our sun room, I fitted a "cat flap tunnel" through the wall.

 

I had ordered the cat flap but it had not arrived.  The quoted dimensions were 19.5cm high and 18.5 cm wide.  I had assumed * that was the overall size of the unit and the actual flap would be smaller.  I made the tunnel 18cm wide, constrained by being in between 2 studs.

 

The flap arrived today.  The actual flap is 18.5cm wide so of course won't open into an 18cm wide tunnel.

 

*Assume = An Ass or You and me.

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how are you planning on maintaining air tightness with the cat flap? I see airtight flaps are crazy money (https://www.petwalk.at/shop/doors) available also from @craig @ Ecowin (https://www.ecowin.co.uk/products/petwalk/) (although I have to say they do look pretty darn cool!).

 

I was planning on having one flap on a door into the garage and then another flap on an external door from the garage outside. the other option is to build a deep tunnel through the wall so that there are 2 x flaps through the tunnel, one at the start and one at the end so that only one flap is open at a time. 

[craig]

  On 16/04/2021 at 12:46, Thorfun said:

I see airtight flaps are crazy money

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Not cheap that's for sure but when you have an airtight house, you want a product that does the job. Designed and built specifically for Passive Houses, it is the only properly airtight pet door on the market that I'm aware of. 

 

  On 16/04/2021 at 12:46, Thorfun said:

(although I have to say they do look pretty darn cool!).

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They are that.

[Thorfun]

  On 16/04/2021 at 12:54, craig said:

 

Not cheap that's for sure but when you have an airtight house, you want a product that does the job. Designed and built specifically for Passive Houses, it is the only properly airtight pet door on the market that I'm aware of. 

 

 

They are that.

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I'm waiting for them to integrate a video camera to check for mice/birds in our cat's mouths and deny/allow entrance accordingly. then I'll be all-in for one!

[craig]

I'll have a chat with Klaus lol 

[ProDave]

  On 16/04/2021 at 12:46, Thorfun said:

 

how are you planning on maintaining air tightness with the cat flap? I see airtight flaps are crazy money (https://www.petwalk.at/shop/doors) available also from @craig @ Ecowin (https://www.ecowin.co.uk/products/petwalk/) (although I have to say they do look pretty darn cool!).

 

I was planning on having one flap on a door into the garage and then another flap on an external door from the garage outside. the other option is to build a deep tunnel through the wall so that there are 2 x flaps through the tunnel, one at the start and one at the end so that only one flap is open at a time. 

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This is not a re run of the passive cat flap thread, 

 

The main house is air tight and mvhr ventilated and there was no way I was having a cat flap in that.

 

The sun room is an add  on at the back, think of conservatory with a roof, or Orangery.  It is not as well sealed and not part of the mvhr system, so it's windows have trickle vents.  It is joined to the main house via a pair of Rationel French doors, so exterior doors thought hey will never see any weather.

 

So the sun room being separate can tolerate a dirty great hole in it that would kill any air tightness.  I think a good compromise to solve the cat flap conundrum.

[Thorfun]

  On 16/04/2021 at 13:40, ProDave said:

This is not a re run of the passive cat flap thread, 

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whoops! sorry. I hadn't got to that part of the forum yet in my research. my apologies!

 

  On 16/04/2021 at 13:40, ProDave said:

So the sun room being separate can tolerate a dirty great hole in it that would kill any air tightness.  I think a good compromise to solve the cat flap conundrum.

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but how to the cat(s) get from the main house to the sun room? I guess they just stand at the doors and shout loudly at you to open them? that's what our cats do whenever they want something

[Onoff]

  On 16/04/2021 at 12:46, Thorfun said:

 

how are you planning on maintaining air tightness with the cat flap? I see airtight flaps are crazy money (https://www.petwalk.at/shop/doors) available also from @craig @ Ecowin (https://www.ecowin.co.uk/products/petwalk/) (although I have to say they do look pretty darn cool!).

 

I was planning on having one flap on a door into the garage and then another flap on an external door from the garage outside. the other option is to build a deep tunnel through the wall so that there are 2 x flaps through the tunnel, one at the start and one at the end so that only one flap is open at a time. 

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All very nice if you're filthy rich.

[Thorfun]

  On 16/04/2021 at 13:50, Onoff said:

 

All very nice if you're filthy rich.

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just realised my post sounded like I was planning on two of the passive house flaps! but when I mentioned 2 x flaps I was talking normal flaps that cost £30 from the local pet shop.

 

unless you were just making an obscure reference to this of course. https://en.wikipedia.org/wiki/Filthy_Rich_%26_Catflap

[newhome]

  On 16/04/2021 at 13:53, Thorfun said:

unless you were just making an obscure reference to this

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Indeed he was ?. @Onoff’s references are often obscure. You’ll get used to him eventually ?

[newhome]

  On 16/04/2021 at 12:39, ProDave said:

Assume = An Ass or You and me

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Or ‘assumption is the mother of all f... ups’ ? 

 

 

[Onoff]

  On 16/04/2021 at 13:58, newhome said:

Indeed he was ?. @Onoff’s references are often obscure. You’ll get used to him eventually ?

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@newhome gets me! ?

[Thorfun]

  On 16/04/2021 at 14:01, Onoff said:

 

@newhome gets me! ?

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is that a good thing? ?

[Onoff]

Is there any merit in standard cheapo cat flaps with a slightly too tight, tinfoil tunnel. The cat has to squeeze its way through. You could recover the heat as it struggles through, to offset the losses...

 

 

[ProDave]

A friend of mine had a cat flap tunnel through the wall with a cat flap at each end, which he claimed cut down heat loss a bit.  A sort of cat air lock.

[markc]

Interestingly, ive been thinking about this recently .... how will we keep air tight and maintain cat comforts? ... still no plot, no idea where, no idea on house design etc etc. but thought going into the cat flap/s

[ProDave]

  On 16/04/2021 at 13:43, Thorfun said:

but how to the cat(s) get from the main house to the sun room? I guess they just stand at the doors and shout loudly at you to open them? that's what our cats do whenever they want something

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The cat has to stand at the French doors, look cute, without a mouse in it's mouth and request entry to the main house.

[Thorfun]

  On 16/04/2021 at 14:11, ProDave said:

The cat has to stand at the French doors, look cute, without a mouse in it's mouth and request entry to the main house.

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I think we need to take a leaf out of your book. we're getting about 3 or 4 mice a day at the moment being brought in. 

[ProDave]

  On 16/04/2021 at 14:20, Thorfun said:

I think we need to take a leaf out of your book. we're getting about 3 or 4 mice a day at the moment being brought in. 

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The sun room will have an easily cleaned tiled floor and will be the only room the cat can access without asking.  Most nights she sleeps there anyway so has enjoyed free access for her nightly patrols, and most mornings there are signs of successful hunting.

[MJNewton]

  On 16/04/2021 at 14:09, ProDave said:

A friend of mine had a cat flap tunnel through the wall with a cat flap at each end, which he claimed cut down heat loss a bit.  A sort of cat air lock.

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Yes, that's what we've got. With brush seals it obviously can't be airtight but holding my hands next to it when it's windy certainly shows there's no draught coming through.

 

Our house isn't 'air tight' though so we only had to be sensible with how we made a hole through the wall. It is in an open plan Family Room though - next to a sofa! - so even the slightest of draughts would've been unacceptable.

Edited April 16, 2021 by MJNewton