Conservatory, garden room or extension for a small rear addition?

[AsteriaBuffy]

Would appreciate any tips as to where best to start as haven't done this before :)

We want to add a single 'garden' room off the back of the house, sticking out into what is now the patio. Size 9 feet by 9 feet, insulated and with electrics. A lot of glass on at least 2 of the sides, and some windows on 3rd side.

It would be about half the width of the back of the house. French doors are already in right position on back of house, so they would stay, and open into the new room.

Not sure whether to go for a traditional conservatory / wooden garden room type structure, or go for something more properly 'built' with brick walls and foundations.

I'm guessing the built structure would be more £££. Is there anything else worth taking into account?

As far as I can see we wouldn't need Planning as more than 2m from boundary, and single storey. Looks like all options would need Building Regs approval as attached to the house.

WWYD?

Would it make the room dark that is currently there?

We had a conservatory put on, around 5 or 8 years ago or something like that, not big, like yours, think it was the maximum size we could have for permmitted development. Glass roof as we wanted the sky to be visible. Our garden is a postage stamp and north facing. We needed the current dining room not to be compromised by reduced light

Best thing we have done to the house by a long way. We do use it all year round as we have a small oil filled rad in there which heats the room nicely. I have a wool underlay that I bought and cut it to fit and then a thick jute rug on top of that. Normal living room furniture in it, its bright and light, open, full glass apart from the old house wall and the wall up against the fence.

ooh @likelysuspect that sounds nice! Cosy as well as light and bright.

Yes I guess light through the roof is a big consideration.

New structure would be off the dining room which is v light (at the moment) as SW facing and open to the kitchen which also has a big window. But it would be a shame to cut out too much light with a completely solid roof. Hmm.

I would post a picture but dont want to!!

So, we have a white sofa with blue thin stripes from DFS many years ago, we have a wing back armchair in a similar fabric, I have seaside stripes on cushions, tons of cushions, with the folky look cushions as well from Ikea.

A smaller armchair, pale wood with the cushion with a sort of soft folky design, then a soft grey footstool and then the big Ikea square white storage footstool. Side tables and lamps everywhere

It is warm and cosy and bright and light and seasidey. Its the best room in the house. More jute rugs on top of the other jute rug and mats by the french doors that go out into the garden.

We have a 1980s type sunlounge on the back of our house. 3 walls are half brick, half window. Solid roof. It's fine temperature wise all year round. But the dining room it joins in to is dark even on bright days.

So you're weighing up light indoors with usability. I know some people say conservatories are too warm in summer, too cold in winter.

Although maybe it depends on the position to the sun how mught light gets into the inside room?

We had a conservatory here with 2 full walls of windows and glass roof. it was in a south facing garden and it was too hot to be in for parts of the summer. During the heatwave 2 years ago it got so hot it broke my garden thermometer.
We’ve since changed it to a solid roof and lost 2 of the windows on one side and apart from it being a tiny bit cold on a January morning (electric heater sorted that), it’s been great.

Downside is the loss of light - ours is the whole width of our house so both kitchen and living room open in to it and both rooms are a fair bit darker than they were before.

For us the loss of light was worth it but you may not have the same temperature issues as we did as it’s SW rather than S facing.

Another option would be solid roof with a lantern or velux windows maybe?

We added a glass roof conservatory afew years ago. We have put in a radiator off the gas mains and got blackout Hilary blinds. We use it most of the year save for heat waves.

Thanks for all the replies and info, much appreciated :)

Think we're leaning towards a conservatory of some sort with low walls, but need to look into all the options for walls, roof, glass - well everything I guess 😅

I added a full glass double glazed garden room. It worked really well - didn't lose any light from the house as all glass and the front and side glass slid completely open when required so it didn't get too hot in the summer. We were able to keep it lovely and warm with a bioethanol stove. It was very simple to install - just went on top of our patio and didn't need planning or building regs so made it very cost effective.

We had an extension, the width of the back of the house, put on within permitted development. It extended the kitchen and dining room, with the dividing wall knocked down (RSJs in as needed) into a large kitchen diner. We had two velux windows put in the pitch roof, to improve the light at the back of the room, the original part of the kitchen diner. It’s all fine. The temperature is the same as the rest of the house, but then the back faces north.

We put in a good quality conservatory 10 years ago, special glass, thick double glazing small walls and DH dug out extra deep to put in really dense insulation.

It is really lovely but with electric underfloor heating it is expensive to heat in the winter.

If I was doing it now I would build a brick built orangery (loads of windows) with a large lantern roof or massive velux on a sloping roof.

You won't need building regs for a conservatory or for a garden room either unless it's massive or close to the fence and big.
I think existing dark room will be your main issue, even with a glass roof it makes a difference, although perhaps SW facing will help there. Imagine an overcast winter day, you'll have the lights on at midday. Also the other is whether you want a knock though, if so it will need a proper building regs compliant extension.

Proper extension is the best in my view but only if it doesn't cover the only window in the other room. No other option really I think.

@AsteriaBuffyI would not have glass on 3 walls and certainly not dwarf walls. Very dated and you need to think about what looks good. We have an oak framed conservatory with a glass roof - it’s my kitchen. It can get hot in summer even though the full glass walls face north and east. The sun comes through the roof. However every morning I think it’s wonderful to see the sky!

Ours has 2 sets of French doors - decided not to have bifolds because they would not really suit the house, but you need a throughput of air and you need the roof to open too.

In order to make it less dark in adjacent rooms, (mine joins the hall and a dining lounge), I just would not have doors and thresholds. I think opening up the back of the house gives you far more light than a door configuration with a threshold. Our conservatory has seemless level flooring with the 2 adjoining spaces and has the same floor as the hall and I’d recommend a level floor and the same flooring as the adjoining room. Mine has a big opening to the hall and the dining/lounge so it’s semi open plan. It has underfloor heating - radiators could work but not if you’ve too much glass!

I would have an “extension” with foundations. Ours does because it has to work structurally with the existing house. You need high quality insulation and the best quality glazing. Any old double glazing won’t do. Consider a solid roof with roof lights or a big lantern with opening sections. A good conservatory is not cheaper than an extension. If it’s cheap it won’t last. We found out the hard way!

Thanks for all the comments, lots to think about, it's really helpful :)

@MeetMeOnTheCorner you've got me googling oak framed conservatories now! Spendy but gorgeous.

OK leaning away from dwarf walls now. It's important that it not only works with the space / temperature, but looks good and potentially adds value. We're doing a separate extension where the garage is (to side and back of house) so it would be good if it all tied in style-wise somehow.

It's a brick-built 50s house, will maybe post a pic tomorrow when I'm more organised.

At our last house we inherited a small-windowed (single glazed) crap extension/conservatory hybrid. I believe the person who built it ran out of money, as it had deep foundations, but a leaky patchwork polycarbonate roof. We decided to keep it but make improvements.

During 2022 we tackled the job, DIYing everything except the replacement slate roof, building new oak framed double glazed windows from scratch ourselves.

It was originally a room with no function, leading off the kitchen. We moved the kitchen to the old living and dining rooms which we knocked through. The old kitchen became the dining room, which admittedly was darker as a result of the adjacent solid roof (in hindsight we should have added skylights), whilst the extension became our living room.

Here's some pics.....

This was the before...

@LibertyLily I think that’s stylish but agree about roof lights. It’s light that makes adjoining rooms lighter.

@AsteriaBuffy To add value, it has to be a proper permanent building. Low cost cheap materials don’t last and it must have effective heating. We used Prime Oak and, yes, they are expensive. Modern well insulated buildings are great too.

Yep, I agree re darker, but we felt the dining room could take being dark/cosy as we mainly used it in the evenings (except Christmas etc), using the kitchen to eat in during the day. So we leaned into the atmospheric vibe with vintage candelabra hanging over the table and panelled walls painted in a saturated colour.

We have a garden room at the back of our house, off the sitting room (bought it like this) with 2 sides glass but a tiled roof. A big difference will be which way your extension will face.

this one faces south but due to the roof and an ornamental cherry nearby we dont get a lot of direct sun in summer during the day because the sun is too high. However we do get the sun shining in during winter when its lower and have blinds that we use then.

it does have electric u/f heating but its very expensive so we just use an oil fired radiator in winter when required. We use ours as our main dining room and hobby room.

this is the second conservatory ive had and i love them. In summer when its hot just open all the doors and windows and if the weather is that good we would be out eating and drinking in the garden anyway.

its worth paying as much as you can to get a ‘proper’ room.

Forgot to add photos.