Cat flap in new build

[Marcus]

Hi all,
I have a feeling this was discussed back in the old place but don't recall for sure, and a quick search for cat flaps on here didn't find it.

I'm working on a self build house and would like a cat flap somewhere without too much compromise on the heat/ draughts front.

I didn't think about cat flaps when the doors and windows were ordered so they are all glass and triple glazed.

I guess it's not practical to cut a hole through a toughened TGU, so it's either get a small downstairs window tgu made with a cat flap (utility room perhaps) or go through the wall - about 17" :- 2 x 4" blocks, 6" cavity, external cedar cladding and internal d&d plasterboard.

My gut feeling is the a new tgu would be easier, though not necessarily cheaper, and possibly more heat-leaky.

Any ideas? Tips?

[Mr Gus]

Heated celotex type box antechamber?

ie exterior attached cat box "le tunnel" with a two way p!astic lined thinner hinged piece that can be pushed by "mr tibbs" with a covered electric heat mat inside & a pressure mat light with a occupied /vacant led indicator with a thick seal celotex draught lined acces door to the house through a wall, such as a inner porch area, whilst it doesn't necessarily have to offer free inner house access (unless incorporated as a twin access heated tunnel, it would be a sealed, slightly raised safe place for your mogwai offering a comfortable waitng spot for the little man / madam whatever the weather.

Regular cat flaps simply pish heat, allowing draughts noise & a lack of security.

Nb any idea go's to hell if your cat gets dominated by other local felines taking over territory.
A canadian friend made a plastic lined celotex type heated outdoor cat igloo for her cat in Canada for the reason of her work shifts & a cats whimsy where coming in when called is concerned, meant added security for her rented home & optimum cat comfort, though it did enjoy it a little too much.
She may have put in a viewing window so she could see if occupied or not from inside the house onto the covered porch where it was placed our of the snow.

Armourflex cable to a plug socket, elevated "hot box" cat kennel with an insulated push flap access that dealt with canadian seasonality.pretty neatly
Clamped assembly with whatever the correct name for parfait / kilner jar closures are, a gasketed version of a roadies flight box.
I have no idea of proper air temperature attained as we lost touch many years ago, but you know how cats are with a heat spot / shed / garage access.

If I still had a ginger prince to be slave to this is how we would have upped sirs comfort levels, unfortunately I still haven't come across a cat to replace him 14 years later, so loaded with character was he! friends with the bird, beater up of big dogs, brocolli, beans & cheese eating spectacles wrecker,shoulder perching in cars (& vet visits) ginger tom who found me miles from his original home. (couldn't not climb in vans) ..."The mung"
(so its lucky we have a bat eared cattish french bulldog "monsieur le tank" )
Being solid plastic sheet lined glued & silicone edge sealed it was easy maintainance (she was very capably crafty) as a single mum & devout cat lady who chose her house as to how the covered porch could look for the halloween month, great girl

[Marcus]

Hmm... well, that's a thought. TBH at this stage I'm still hoping i can get a flap installed, rather than shutting in or out.

The new ASHP is no heating the house and the cat has suddenly become reluctant to leave, so she's liable to be shut in all day when I'm working.

[nowty]

My door / window supplier gave options of pre-cut insulated panels to go into the uPVC units in place of a glass panel.

[Mr Gus]

The insulation thickness for our front door is so naff as to be pointless, I cannot imagine then cutting an additional hole in it.

OP, an ante chamber cat box can have 2 entrances, you'd just design it to be as insulated & draught proofed as possible, maybe by ensuring draughts cannot simply flow straight through via a baffle that the cat simply moves around.

[Marcus]

Part of the reason my doors are all glass is that i was told that the non-glazed panels were worse U value than the glass, and the frame was worse than either, so the doors are all one single tgu. I don't really want to replace an entire pane in the utility either, hence my thinking of a tgu with a flap built in.

But perhaps the hard work option (tunnel through the wall with a flap at both ends) is the best then - possibly with gus's extra antechamber.

I guess i 6" core drill would make a big enough hole and it could be lined with a bit of pipe.

[Moxi]

Our cat flap install is like Nowty's but when we have Westerly Gales we have to lock it otherwise the wind overwhelms the magnetic catch and blows it open letting a stream of cold air in. When its locked we bung in some bubble wrap thats shaped to the port to add airtightness, same for the letter box, - its ok and works well for us but bear in mind we spend 11 months of the year with the bedroom windows open about an inch and the other month pulled to but not latched unless its gales, so we are not attempting passive house standards.

I assume the cats too old to learn new habits ?

Jaffa knows to meow at the locked cat flap in Gales and I go down and let him in - if he's in and its windy he knows to stay in and uses a temporary litter tray that is deployed in such situations for his requirements.

Moxi

[Marcus]

... I assume the cats too old to learn new habits ? ...

Evidently not: as it's a newbuild and unheated until now, me and the cat are living in a touring caravan - at this time of year it's typically a few degrees above freezing in the mornings when we get up and the cat is either on or in the bed depending on temp.

But as the last two days were sunny here I've been running the hp off the solar and now the house is at 18° and only drops a degree or so overnight, so she's unilaterally decided it's time to move in, and apart from a 5min foray this morning she didn't want to go out. She does call to be let in or out (of the caravan) but i don't like to leave her shut in, and don't really want to leave a window open for her like i do in the caravan when not there.

Also, when i have moved in, it is unlikely that I'll be able to hear her calling to be let in through triple glazing, so a permanent solution is needed.

[Mr Gus]

Whereas "the Mung" used to sit / slide on the upvc windowsill, then meow (marcel marceux like) & scrabble at the window until we..

A. opened a window for his majesty to climb / saunter / glare at.
B. went to the door & whistled him in (good for distance)
C. went out in the rain to pick him up from the windowsill about 20 foot away because sir didn't want wet paws.

It's a cats life indeed.

[spread-tee]

We have one of those electronic chip activated flaps for "Offcut" which when locked doesn't get blown open even with the wildest wind. When new before the seals around the flap get too grotty it is reasonable wind proof, and TBH I accept the small airleak as part of the adventitious air required for the well being of the house.

Desp