My garden Room Build

iwillhtfu

RobAMerc wrote: »

Prices are getting saucy ! but I think I am still in good stead to make it for under 5k - but its gonna be tough ( mainly coz of the sparky ! )

You could wire that yourself not a bother there isn't much to it. The most awkward part will be running a cable back to the board in the house and if you're doing that you may aswell run some comms cable back to the router also. The cheapest has probably planned to wire back to the nearest socket.

NIMAN

op

Have you a design you are basing this on?

Then again, perhaps we shouldn't see it, spoil the surprise of the finished product.

RobAMerc

NIMAN wrote: »

op

Then again, perhaps we shouldn't see it, spoil the surprise of the finished product.

exactly ! I cant wait to see what its going to end up like !

Really no - I woke up this morning and designed the roof in 10 mins and built it.
The overhangs changed size about twice during the day based on wood use and how it looked.

RobAMerc

iwillhtfu wrote: »

You could wire that yourself not a bother there isn't much to it. The most awkward part will be running a cable back to the board in the house and if you're doing that you may aswell run some comms cable back to the router also. The cheapest has probably planned to wire back to the nearest socket.

( dont let anyone from the Electrical forum read this :eek: :eek: )

bar the wiring into the consumer board yes I could - and based on me being told to use 3 different spec's of wire, there is a good chance I'd get it right, or as right as some of them

I think it needs a bit more than a spur off the kitchen though.

iwillhtfu

RobAMerc wrote: »

( dont let anyone from the Electrical forum read this :eek: :eek: )

bar the wiring into the consumer board yes I could - and based on me being told to use 3 different spec's of wire, there is a good chance I'd get it right, or as right as some of them

I think it needs a bit more than a spur off the kitchen though.

Yeah I'm waiting to be eaten alive for that but I can't imagine you're going to have much running out there. A few sockets some down lights inside and maybe in the overhang. If you're going to the trouble of wiring back to the main board a small DB in there would make sense albeit overkill.

RobAMerc

no, probably a laptop, telly maybe a PS4 and some down lighters - but a heater is what I am worried about.

iwillhtfu

RobAMerc wrote: »

no, probably a laptop, telly maybe a PS4 and some down lighters - but a heater is what I am worried about.

You'll probably be somewhere between 2A and 10A depending on the heater you choose I assume it's a panel heater you're looking at. The other things you mention will have a small draw particularly if using LED bulbs.

Price up the cable and see which size suits your needs if the price is negligible the bigger will future proof you. You've probably had quotes for 2.5/6/16sqmm incoming cable supply.

looksee

When I had a shed wired for power, computers, lights etc the electrician insisted the best job was to put in a box just where the wires left the house for the shed - and cut out a channel in the concrete path, then buried the cable.

Lumen

Cable and switching is cheap, so it makes no sense to skimp.

Mine was done with a new 20amp mains supply from existing house consumer unit to new distribution board in shed complete with main switch, 20amp RCBO & 16amp MCB.

Whatever the hell all that means.

The armoured cable was buried in a 600mm trench.

Proper ducting is also cheap.

It's the labour which is expensive.

iwillhtfu

Lumen wrote: »

Cable and switching is cheap, so it makes no sense to skimp.

Mine was done with a new 20amp mains supply from existing house consumer unit to new distribution board in shed complete with main switch, 20amp RCBO & 16amp MCB.

Whatever the hell all that means.

The armoured cable was buried in a 600mm trench.

Proper ducting is also cheap.

It's the labour which is expensive.

20A RCBO to cover the sockets
16A would be used for lighting & small power. I'd keep them separate myself but they may have only installed a small enclosure and had limited space.

What size SWA did they use and how long was the run? I'd have thought 6sq would suffice here possibly 10sq if the run was particularly long but no harm to have the 10sq if cost was negligible.

OP you could always pull in the supply cable yourself as pointed out if you intend on burying the cable that'll be a fair bit of work.

Rows Grower

That tree nearest the roof doesn't look the safest, I'd be dropping that in case it does a bit of damage in the next storm.

RobAMerc

Well, this is what I was told "One 32A main switch at house main board.
1 armored cable 4 or 6mm(buried where possible)
1 small sub board at office with 10A breaker for lights, 20A RCD(protection device) for sockets and 10A breaker for flooring."

This was before I changed to go with Panel heater as I am told the underfloor electric mats are sh1te - I dont think it will change too much though.

Its a 55m run from the board in the house to the room.

Another suggested no sub board and 2.5 mm cable "would be loads"

btw - that much 10mm cable is €450 from screwfix, there must be cheaper !

listermint

RobAMerc wrote: »

Well, this is what I was told "One 32A main switch at house main board.
1 armored cable 4 or 6mm(buried where possible)
1 small sub board at office with 10A breaker for lights, 20A RCD(protection device) for sockets and 10A breaker for flooring."

This was before I changed to go with Panel heater as I am told the underfloor electric mats are sh1te - I dont think it will change too much though.

Its a 55m run from the board in the house to the room.

Another suggested no sub board and 2.5 mm cable "would be loads"

btw - that much 10mm cable is €450 from screwfix, there must be cheaper !

try a proper electrical supplier like https://www.eurosales.ie/ or kellerhers ballymount

iwillhtfu

RobAMerc wrote: »

Well, this is what I was told "One 32A main switch at house main board.
1 armored cable 4 or 6mm(buried where possible)
1 small sub board at office with 10A breaker for lights, 20A RCD(protection device) for sockets and 10A breaker for flooring."

This was before I changed to go with Panel heater as I am told the underfloor electric mats are sh1te - I dont think it will change too much though.

Its a 55m run from the board in the house to the room.

Another suggested no sub board and 2.5 mm cable "would be loads"

btw - that much 10mm cable is €450 from screwfix, there must be cheaper !

10sq would probably be overkill imo unless you plan on turning it into a garage/workshop (think big motors). I'd go for the 6sq over the 4 anyway but definitely get a price from a wholesaler not screwfix.

Have you a panel heater in mind? It'll have a power rating (watts) on it (power (W)/voltage=current(A)) to give you an idea of the loads you'll be drawing so a 2000w heater will be in and around 8-9A at peak load and less if only using at a lower setting.

Lumen

FWIW I believe the permitted alternative to deep burial of the cable is to surface mount it along a boundary wall or fence.

It obvs looks worse but is a lot less effort than digging a 2 foot trench. The first foot is easy....

RobAMerc

iwillhtfu wrote: »

10sq would probably be overkill imo unless you plan on turning it into a garage/workshop (think big motors). I'd go for the 6sq over the 4 anyway but definitely get a price from a wholesaler not screwfix.

Have you a panel heater in mind? It'll have a power rating (watts) on it (power (W)/voltage=current(A)) to give you an idea of the loads you'll be drawing so a 2000w heater will be in and around 8-9A at peak load and less if only using at a lower setting.

Thanks - I was looking at a 450w Eco panel heater - dunno what that means
Eco Panel

Lumen wrote: »

FWIW I believe the permitted alternative to deep burial of the cable is to surface mount it along a boundary wall or fence.

It obvs looks worse but is a lot less effort than digging a 2 foot trench. The first foot is easy....

So, the houses were originally built with a dwarf wall between them, my next door neighbours built a full size wall leaving a 1 inch ish trough between them that I think is ideal for running a cable in. I will then put stones or cement into it to seal - imo I am much less likely to be digging around in there than digging in the garden !

iwillhtfu

RobAMerc wrote: »

Thanks - I was looking at a 450w Eco panel heater - dunno what that means
Eco Panel

Not even 2A at peak load you'll be fine. I'd say there will be no more than 10A peak from what you have planned. Better to be over spec though as you'll most likely have a coffee machine/kettle possibly a small fridge all followed shortly after by your bed and belongings

RobAMerc

any thoughts on NYM-J vs Armoured ? told either is fine but I am thinking NYM-J might be a shortcut too far

iwillhtfu

RobAMerc wrote: »

any thoughts on NYM-J vs Armoured ? told either is fine but I am thinking NYM-J might be a shortcut too far

You'd be thinking right that's cutting corners. It could be argued if it was ducted the entire length of the route what makes it different from what ESB networks though.

You have to consider the person that doesn't know it's there after you've sold the house or are out when someone is doing some work in your garden down.

Twin and earth for the local wiring and SWA for the long run back to the main DB. There could be an arguement for installing an earth rod particularly if the house is old and doesn't already have a rod sunk but the electrical forum will give better specifics it's been along time since I've done any house bashing and standards have changed since.

RobAMerc

thanks - I thought so.
1 sparky said, yes sunken rod - another said no need as there is no plumbing or metal framing.
the house was totally rewired in 2011 and there is an earth rod.

maxamillius

If it was me, I’m a sparks, I’d run a 6sq out there into a subboard, 10A RCBO got lighting, 10A RCBO for sockets,

You never know you may devise to extend the build at some stage in the future, better to have capacity on the cable ie 6sq, 10 is overkill.

Probably best to bury it but it can also be clipped above ground.

Cushtie

Great thread and will be following. Watched some of that guys YouTube aswell. Makes it all look so easy and logical. I would love to be able to do this kind of stuff but am a complete moron when it comes to DIY. The missus breaks out in a cold sweat when she sees me opening the tool box or taking out a drill!!

stiofan85

maxamillius wrote: »

If it was me, I’m a sparks, I’d run a 6sq out there into a subboard, 10A RCBO got lighting, 10A RCBO for sockets,

You never know you may devise to extend the build at some stage in the future, better to have capacity on the cable ie 6sq, 10 is overkill.

Probably best to bury it but it can also be clipped above ground.

this is what I had for something similar except maybe a larger breaker for sockets as I was running some tools. Ended up with a washer and dryer down there and was glad of the peace of mind that the capacity was there. IIRC the price difference for 6sq vs 4sq was negligible. I had a 10-12m run and was well over €100 from an electrical wholesalers, so I imagine your €450 quote for 5x that long is about right.

good luck with the build, enjoying the thread

iwillhtfu

maxamillius wrote: »

If it was me, I’m a sparks, I’d run a 6sq out there into a subboard, 10A RCBO got lighting, 10A RCBO for sockets,

You never know you may devise to extend the build at some stage in the future, better to have capacity on the cable ie 6sq, 10 is overkill.

Probably best to bury it but it can also be clipped above ground.

An RCBO for lighting, Cén fáth?

maxamillius

iwillhtfu wrote: »

An RCBO for lighting, Cén fáth?

No reason other than convenience, MCB perfectly adequate also.

Off topic but I believe we should be using RCBOs entirely as opposed to MCBs alongside an RCD.

Makes for an easier install and also easier fault finding

Darando

RobAMerc wrote: »

Prices are getting saucy ! but I think I am still in good stead to make it for under 5k - but its gonna be tough ( mainly coz of the sparky ! )

Looking great, is it the cladding/insulation that puts your costs up? or the sparks?

Idbatterim

Looks good op, just looked at your op. I'd have used ground screws, far easier... also I'd have doubled up the 6x 2 on the printed, one fir wall to sit on and the other for osb / plywood to sit on

Alkers

With all the disagreement over cabling runs, I would definitely duct the run between the house and the build on case you want to change / upgrade or add things in the future.
Great work btw

RobAMerc

Darando wrote: »

Looking great, is it the cladding/insulation that puts your costs up? or the sparks?

It's all just adding up. Lots of bits i didn't think about originally.
Ive decided top go for pvc cladding for now rather than the cedar. I will come back and do the front facing sides in cedar later but the pvc will have to do for now. Time and money dictate this.

RobAMerc

Idbatterim wrote: »

Looks good op, just looked at your op. I'd have used ground screws, far easier... also I'd have doubled up the 6x 2 on the printed, one fir wall to sit on and the other for osb / plywood to sit on

Have you completed yours? Pics ?

Darando

Contemplating mine but can’t afford a big overrun so just checking where my hidden costs may be.Framing, sheeting seems reasonable from my calcs, it’s insulation and cladding that adds up it seems (leaving out window costs).

RobAMerc wrote: »

It's all just adding up. Lots of bits i didn't think about originally.
Ive decided top go for pvc cladding for now rather than the cedar. I will come back and do the front facing sides in cedar later but the pvc will have to do for now. Time and money dictate this.

listermint

Alkers wrote: »

With all the disagreement over cabling runs, I would definitely duct the run between the house and the build on case you want to change / upgrade or add things in the future.
Great work btw

And not to forget put cat6 in the ducting too.

listermint

RobAMerc wrote: »

It's all just adding up. Lots of bits i didn't think about originally.
Ive decided top go for pvc cladding for now rather than the cedar. I will come back and do the front facing sides in cedar later but the pvc will have to do for now. Time and money dictate this.

Pvc or composite? You'll get a nice finish from a composite. However I believe it may be pricey. I clad my porch add on with ceder. But I picked it up free from connections it came down from an office block. Beautiful stuff and cost me nothing.

Timber framed the porch like yours breathable insulation in walls. All adds up very quickly.

listermint

Darando wrote: »

Contemplating mine but can’t afford a big overrun so just checking where my hidden costs may be.Framing, sheeting seems reasonable from my calcs, it’s insulation and cladding that adds up it seems (leaving out window costs).

You won't put up something like this with a reasonable fit and finish like heat retention etc for less than 5k. That's doing everything yourself bar maybe restricted trade work .. elecs

Even at 5k you'd want to be starting with some tools of your own for all the work.

c.p.w.g.w

In relation to foundation...I can see the OP has the room resting on blocks...How do you protect the floor timbers from rot and damp

RobAMerc

its 6 inches off the ground with DPC lining on the bottom of the timbers, and polythene covering it - the wood is also treated.
The cladding will also come down pretty close to the bottom.
It will be dry under there !

RobAMerc

So I am thinking about the roof - due to the position of the room, as far as I can see the taper in the roof is going look a bit off.

I wonder if anyone on here knows of a way to avoid this.
I going with a 75mm to 0 slope on the roof, this means a fairly large taper down one side as you look at it from the back of my house.

As I am using EPDM I may have some flexibility in how I can build the roof.
here is what I am thinking -
I have a roof trim kerb of about 25mm high and 50mm lip on it, intended to follow the taper and lay flat on the epdm.
My idea is to run another 75 x 75 batten alongside the firrings on one side. I could butt the ply up against this meaning this would be the real kirb on the roof and use flexibility of the rubber and some of the stronger adhesive to shape it over the kerb.
Then when putting the trims on - both would be sitting atop a 75mm batton their full length, giving an equal height fascia on both sides.

Does this make any sense ? Am I leaving myself open for problems creating this dummy kerb and trying to shape the rubber around it ?

thanks

Lumen

How will the water drain off if you have this "kerb"? (parapet?)

RobAMerc

the kerb is on 1 side only running alongside the fall - so the water will drain off the same way as it always would

RobAMerc

maybe this will make sense of it
I dont think its much different to the way modern houses flat roofs look to have no roof at all, there is just a big kirb around it of block

Class MayDresser

Looks good. The bare side of the roof is up against the exterior wall I take it? Why not continue the parapet on three sides? Drain all the roof water as opposed to most of it...
Would the parapet timber have to be a hardwood or commercial strength to withstand year round temperature fluctuations and possible warping? Someone with better experience would know more, they're just the thoughts of an insomniac DIYer.

RobAMerc

Class MayDresser wrote: »

Looks good. The bare side of the roof is up against the exterior wall I take it? Why not continue the parapet on three sides? Drain all the roof water as opposed to most of it...
Would the parapet timber have to be a hardwood or commercial strength to withstand year round temperature fluctuations and possible warping? Someone with better experience would know more, they're just the thoughts of an insomniac DIYer.

No, the whole thing is stand alone. Good question about the parapet - I was going to make it of the same as the rest of the joists, anyone here know the answer ?

RobAMerc

So, I moved it on a bit.

I finished the sheeting of the walls, it was quick and easy.
I orginially order 9mm as I though it would make it easier to put up. TJ didnt have it in stock and only after a bit of moaning from me did they deliver 11mm. It was easy enough to fit anyway.

I then moved on to putting the vapour barrier - and I am not sure its the right way round !

Loking at the doeumentation, it seems to be fine. But I'd like to be sure, so I didnt nail it on too firmly.
Anyone here enlighten me as to how to know ( other than the roll looks the right way round )

Lumen

By "vapour barrier", do you mean the black-faced stuff?

If it's on the outside, it's not a vapour barrier, it's a windtight membrane, and the black face goes on the outside. Is it fleece-backed?

iwillhtfu

What floor covering have you planned for the exposed porch area? It looks as though it might be a bit vulnerable to the rain.

It's coming together well. Have you sorted out a spark yet?

RobAMerc

Lumen wrote: »

By "vapour barrier", do you mean the black-faced stuff?

If it's on the outside, it's not a vapour barrier, it's a windtight membrane, and the black face goes on the outside. Is it fleece-backed?

Yes, breather membrane sorry. Black on the outside, got it - it made sense that the roll would roll out that way.

thanks

RobAMerc

iwillhtfu wrote: »

What floor covering have you planned for the exposed porch area? It looks as though it might be a bit vulnerable to the rain.

It's coming together well. Have you sorted out a spark yet?

I am going to go with composite decking I think with poly sheeting underneath.

yes, got a "sparky" thanks - all the stuff ordered from meteor - thanks to Lumen for the heads up

GreeBo

iwillhtfu wrote: »

Not even 2A at peak load you'll be fine. I'd say there will be no more than 10A peak from what you have planned. Better to be over spec though as you'll most likely have a coffee machine/kettle possibly a small fridge all followed shortly after by your bed and belongings

The wiring spec is as much (if not more) about the drop over the 55M and not just the load.

Get an electrician to spec if and dig the trench yourself.

iwillhtfu

GreeBo wrote: »

The wiring spec is as much (if not more) about the drop over the 55M and not just the load.

Get an electrician to spec if and dig the trench yourself.

I'm well aware of that thanks

RobAMerc

roof decking on - took me WAYyyyyyy longer than I thought and I really dont know what I was at

Was going to try make the firring strips myself but in the end decided to drop up to brookes and buy them. The fall isnt as much as I had hoped.

I bought 75x44 strips thinking they were 4.2m which would have been perfect, but they were 4.8m meaning the drop was 75 to 8-10mm by the time I had cut them down - but its still 1-60 ( by my calcs ) which is enough

Also for some bizzare reason 1 was a mile out and this through out my calcs by a bit meaning the spaceing doesnt look great but is fine.

As you can see I put them up across the joists. I am building a cold roof and therefore I did this to increase airflow across the rafters.

One bit of advice I would give everyone is - if something is in your way stop and take the time to move it rather than being lazy and trying to work around it.
I spent an age trying to work with the tarp on, it made it very difficult but I was just being lazy

Otherwise, its not as hard as you might think

Next, I have to go borrow a ladder and get some help lifting the epdm onto the roof - probably Monday. so any tips welcome !

hope this is useful to someone.