Loft insulation

Following on from the success of the plumbing thread I thought I would appeal to the hive for advice.

I had a recent look around the loft an noticed that when I asked the builder to top up the insulation he had misheard me and thought I asked for a donut arrangment around the hatch rather than covering the entire area.

So I see two choices;

Accept that whilst a technically easy job it is messy so pay somebody and if so a specialist or a handyman

Or man up and do it myself. As a cowboy by nature I look at the advice of topping up the rafters (I have about 100mm) and then going crossways with another layer and wonder why not just put 200mm between the rafters and leave it standing proud.

If it matters it is about 90m2
«1

Comments

  • monkimark
    monkimark Posts: 1,628
    edited May 2022
    I assume you mean joists rather than rafters?
    Don't you want to be able to board it out afterwards so you can store stuff in there?
  • surrey_commuter
    surrey_commuter Posts: 18,867
    monkimark said:

    I assume you mean joists rather than rafters?
    Don't you want to be able to board it out afterwards so you can store stuff in there?

    History tells me that if I put something in the loft then I may as well chuck it so maybe a small area for suitcases.
  • monkimark
    monkimark Posts: 1,628
    The joists/gaps between the insulation will form a cold bridge, which I guess is the logic of overlaying at 90 degrees.
    The two layers at 90 degrees will be better insulating but also more faff. I'd also be wary of hiding the joists as I'd probably end up falling through the ceiling one christmas trying to get to the decorations at the back of the loft.


    As a cowboy by nature I look at the advice of topping up the rafters (I have about 100mm) and then going crossways with another layer and wonder why not just put 200mm between the rafters and leave it standing proud.

  • surrey_commuter
    surrey_commuter Posts: 18,867
    I am reading that for two votes for man up and lay as thick as possible between the joists
  • pangolin
    pangolin Posts: 6,362
    Three
    - Genesis Croix de Fer
    - Dolan Tuono
  • monkimark
    monkimark Posts: 1,628
    edited May 2022
    Yeah, on balance, probably the best option. Not sure I'd even be that bothered about going higher than the joists given there will be gaps every 300mm. You can probably find a u value calculator online to work out the difference in insulation between the 2 options.

    I only have insulation the depth of the joists with chipboard on top so I can store loads of crap I don't need up there but I have my eye on an unused pack of Celotex boards at work to put between the joists and the chipboard to add a bit more insulation. Don't think I'd bother if I had to buy it though as it would probably cost about £500.
  • rjsterry
    rjsterry Posts: 27,916
    monkimark said:

    Yeah, on balance, probably the best option.
    I only have insulation the depth of the joists with chipboard on top so I can store loads of censored I don't need up there but I have my eye on an unused pack of Celotex boards at work to put between the joists and the chipboard to add a bit more insulation. Don't think I'd bother if I had to buy it though as it would probably cost about £500.

    I think the basics have been covered. You can get corrugated eaves trays to make sure you maintain ventilation and get the insulation right to the edge (so you don't have a cold strip of ceiling). Ceiling joists are usually only 2x4 so you won't really get enough depth without a double layer. You can just run some more 2x4 perpendicular to the joists if you want to board for storage. Even semi-skillrd labour seems to want ~£300 a day so make that another vote for DIY.
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition
  • surrey_commuter
    surrey_commuter Posts: 18,867
    Many thanks everybody
  • TheBigBean
    TheBigBean Posts: 20,801
    If you know someone who would do the job well, then I'd vote for just paying for it.
  • rick_chasey
    rick_chasey Posts: 73,169
    Depends on your finances but these things are rarely worth your own effort….
  • morstar
    morstar Posts: 6,190
    Loft insulation is not a skilled job though. Perfectly simple to do yourself and can be turned around from purchase to completion in a couple of days easily. One if it’s a nice easy layout and you’ve got no clutter in there.
    If you have a reliable handyman who you trust to turn up and do it, it’s preferable to have someone else do it as it’s a messy hot job. But waiting for tradesman to be available and actually turn up can be frustrating in its own right. Only to pay through the nose for the privilege.
  • surrey_commuter
    surrey_commuter Posts: 18,867
    Many thanks everybody
  • Pross
    Pross Posts: 41,079

    If you know someone who would do the job well, then I'd vote for just paying for it.

    Yeah, me too. I value my time too much to spend a few hours breathing in insulation material and getting dusty and sweaty in the loft, smacking my head on rafters etc.
  • pangolin
    pangolin Posts: 6,362
    Pross said:

    If you know someone who would do the job well, then I'd vote for just paying for it.

    Yeah, me too. I value my time too much to spend a few hours breathing in insulation material and getting dusty and sweaty in the loft, smacking my head on rafters etc.
    Surely by now you have a mask
    - Genesis Croix de Fer
    - Dolan Tuono
  • Pross
    Pross Posts: 41,079
    Not that type. My loft is a horrible place to be anyway, it's only about 5 feet high at the apex.
  • photonic69
    photonic69 Posts: 2,496
    DIY for sure. It’s easier than recableing a bike.
    Insulation from Wickes along with a pack of loft boards to walk on. Disposable overalls, mask, goggles and gloves from Toolstation. Sharp pair of wallpaper scissors to cut the stuff.
    Easy peasy. Done about four now for myself and family. No more than a days work if loft Is empty.


    Sometimes. Maybe. Possibly.

  • HilaryAmin
    HilaryAmin Posts: 160
    edited May 2022
    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

  • morstar
    morstar Posts: 6,190

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I bought mine about 10 years ago. I wasted an incredibly large amount of time before actually laying it though.

  • surrey_commuter
    surrey_commuter Posts: 18,867

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
  • rjsterry
    rjsterry Posts: 27,916

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    It's funny: we get lots of questions from clients about whether they should invest in an ASHP or photovoltaic panels, but very few are interested in spending money on insulation.
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition
  • surrey_commuter
    surrey_commuter Posts: 18,867
    rjsterry said:

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    It's funny: we get lots of questions from clients about whether they should invest in an ASHP or photovoltaic panels, but very few are interested in spending money on insulation.
    maybe you could let them live in a modern house for a week so they could see the difference
  • Pross
    Pross Posts: 41,079
    rjsterry said:

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    It's funny: we get lots of questions from clients about whether they should invest in an ASHP or photovoltaic panels, but very few are interested in spending money on insulation.
    Aren't most people already pretty much as insulated as they can be? We could probably go deeper with our loft insulation (although it would involve ripping up all the loft boarding) but I'm not sure what else we can do. It was assessed back when my daughter was having chemo as we were eligible for a grant, the only thing they picked up on was cavity wall insulation and when the company came to do it they discovered it was already done.
  • TheBigBean
    TheBigBean Posts: 20,801

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
  • surrey_commuter
    surrey_commuter Posts: 18,867

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
    My Dad is a complete socialist who used to rage against Maggie's privatisations as buying something we already owned. He happily filled out the forms in different family memmbers names on the grounds that if they were going to sell him somethig he already owned cheaply then he would happily buy it.

    If I remember correctly the first one was for BT and they did not put a minimum age of 18 in the prospectus.
  • TheBigBean
    TheBigBean Posts: 20,801
    edited May 2022

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
    My Dad is a complete socialist who used to rage against Maggie's privatisations as buying something we already owned. He happily filled out the forms in different family memmbers names on the grounds that if they were going to sell him somethig he already owned cheaply then he would happily buy it.

    If I remember correctly the first one was for BT and they did not put a minimum age of 18 in the prospectus.
    That's an argument that you'll take the money if it is available, but you wrote "this is far too sensible" when discussing subsidies. Surely, you don't think any subsidies are good?
  • surrey_commuter
    surrey_commuter Posts: 18,867

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
    My Dad is a complete socialist who used to rage against Maggie's privatisations as buying something we already owned. He happily filled out the forms in different family memmbers names on the grounds that if they were going to sell him somethig he already owned cheaply then he would happily buy it.

    If I remember correctly the first one was for BT and they did not put a minimum age of 18 in the prospectus.
    That's an argument that you'll take the money if it is available, but you wrote "this is far too sensible" when discussing subsidies. Surely, you don't think any subsidies are good?
    it is an acceptance that he is going to spend tens of billions of pounds, in which case paying for people to insulate their homes before winter seems like a good idea
  • rjsterry
    rjsterry Posts: 27,916
    Pross said:

    rjsterry said:

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    It's funny: we get lots of questions from clients about whether they should invest in an ASHP or photovoltaic panels, but very few are interested in spending money on insulation.
    Aren't most people already pretty much as insulated as they can be? We could probably go deeper with our loft insulation (although it would involve ripping up all the loft boarding) but I'm not sure what else we can do. It was assessed back when my daughter was having chemo as we were eligible for a grant, the only thing they picked up on was cavity wall insulation and when the company came to do it they discovered it was already done.
    Not even close. IIRC roughly half of the existing housing stick is still uninsulated 9" brickwork with single-glazed sash windows and 4" of raggedy fibreglass in the loft. Yes, it is sometimes more difficult to add insulation and you either need to lose a small amount of floor area or change the external appearance of the house, but it's all doable.
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition
  • rjsterry
    rjsterry Posts: 27,916

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
    My Dad is a complete socialist who used to rage against Maggie's privatisations as buying something we already owned. He happily filled out the forms in different family memmbers names on the grounds that if they were going to sell him somethig he already owned cheaply then he would happily buy it.

    If I remember correctly the first one was for BT and they did not put a minimum age of 18 in the prospectus.
    That's an argument that you'll take the money if it is available, but you wrote "this is far too sensible" when discussing subsidies. Surely, you don't think any subsidies are good?
    it is an acceptance that he is going to spend tens of billions of pounds, in which case paying for people to insulate their homes before winter seems like a good idea
    Exactly. Pay everyone to insulate their home > no more grannies freezing to death; pay everyone's gas bill for a year and you just put the problem off for 12 months.
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition
  • pangolin
    pangolin Posts: 6,362
    .
    rjsterry said:

    Did mine over ten years ago when B&Q were charging £3 for a large roll - in today's money roughly 2 loaves of bread. Appropriately ISTR cutting it with a breadknife.

    I am hoping the Govt will put huge subsidies into insulation.

    I accept this is far too sensible to be a realistic possibility but it would be very annoying if it was announced days after I paid £400 for the stuff
    This isn't the sort of pure free market view I would have expected.
    My Dad is a complete socialist who used to rage against Maggie's privatisations as buying something we already owned. He happily filled out the forms in different family memmbers names on the grounds that if they were going to sell him somethig he already owned cheaply then he would happily buy it.

    If I remember correctly the first one was for BT and they did not put a minimum age of 18 in the prospectus.
    That's an argument that you'll take the money if it is available, but you wrote "this is far too sensible" when discussing subsidies. Surely, you don't think any subsidies are good?
    it is an acceptance that he is going to spend tens of billions of pounds, in which case paying for people to insulate their homes before winter seems like a good idea
    Exactly. Pay everyone to insulate their home > no more grannies freezing to death; pay everyone's gas bill for a year and you just put the problem off for 12 months.
    Give a man a fire, he'll be warm for a night.

    Set a man on fire, he'll be warm for the rest of his life.
    - Genesis Croix de Fer
    - Dolan Tuono
  • rjsterry
    rjsterry Posts: 27,916
    oxoman said:

    Problem is some older houses don't lend themselves to being externally insulated and look horrible after. ( sorry bro ) his gaf looks horrible. Some can't be done because there listed etc. A lot of the time when surveyors do an area survey they just give a generic look and copy and paste for everything else. The only way I can improve my place is triple glazing and fitting a heat pump system. The air type aren't particularly long laptop efficient. I've overinsulated the loft and loft conversion have cavity wall insulation even though built pre 1900 and double glazing, fancy rad valves and heating system etc but it still doesn't get me a better rating unless I actually move. PS I was always told if its cold close the door / windows or put a jumper on. People expect to much. However as per the OP get it done it doesn't cost a fortune and is easy to do.

    EPCs are so basic as to be aimed useless. External insulation isn't always appropriate, but in that case there's either cavity or internal insulation. Listed proprietors aren't off limits either with a bit of thought. I know of one example that achieved Enerphit (similar to Passivhaus) certification. It's not necessarily easy, but then a heat pump is £8-£10k and will struggle without upgrading the fabric.
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition