Anyone have the MBC open panel 140mm wall system?

[Thedreamer]

@Dreadnaught I used the sister product for the membrane on the OSB exterior, it held up reasonably well. Had to do some patching but this was mostly due to wear and tear rather than the quality of membrane.

 

This one and the VCL layer are marketed as having thermal properties but do they actually offer much here? ? Does this form part of the thermal wall calculation?

 

And I sometimes sit on my 'Quintherm sofa' and I don't hear any baa baa coming from the croft, so I'm glad I increased the spec and went for triple glazed windows. 

 

 

 

 

 

 

Edited January 5, 2019 by Thedreamer

[lizzie]

26 minutes ago, Dreadnaught said:

 

Your usual observation is very welcome. Through your repeated emphasis on the such matters I have learnt so much.

 

Here's the conundrum. In my design, most of the walls of my bungalow will be shaded by an overhanging simple pitched slate roof. Thus, sun's energy that could risk overheating in the summer predominately falls on the roof. Now here's the key part. The section I showed above is only for the walls, the roof is different. The roof system that MBC specifies to go along with the 140mm open stud wall system has 400mm of blown-cellulose insulation (see below). Thus, I am putting the cellulose in the place it is most needed for enhancing decrement delay, the roof. 

 

Thus I am getting the best of both worlds, while also reducing panel bulk, and saving the 30% price premium. Am I right?

 

From MBC again …

 

My roof is 0.10 with the 400mm insulation although a completely different structure......beware the 25mm service cavity batten if you are going to put in downlights, mine was not deep enough caused chaos we had to double batten to increase the space which meant I lost a few cm of ceiling height, it was too late to do anything about it.

[Dreadnaught]

17 minutes ago, lizzie said:

My roof is 0.10 with the 400mm insulation although a completely different structure

 

@lizzie thanks. Can I just check that it is 400mm of blown-cellulose insulation in your roof? Did they come along with the blowing machine and cut disks into your ceiling to blow it in? Its not some sort of cellulose batt that they used?

 

It does seem a bit odd to me that they would go through palaver of bringing the cellulose blower to site just for the roof.

 

Good point about the ceiling service-void and downlighter. I must remember to watch out for that.

 

 

Edited January 5, 2019 by Dreadnaught

[Jeremy Harris]

Our ceiling battens for the service void are 50mm, like the external wall service void battens, so plenty of room to fit slim panel lights.  When our house was built 50mm x 50mm service void battens were the standard, so I doubt there would be any real hassle in changing to these.

[Nickfromwales]

13 minutes ago, Dreadnaught said:

Good point about the ceiling service-void and downlighter. I must remember to watch out for that.

Different types of downlights can have much shallower depths

I personally prefer the led flat panel ( 180mm round ) LED types nowadays, and the light is just spectacularly better than a single small spot. There are instances where I will still fit a 'regular spotlight' but they need to be a nice looking fitting with no horrible visible clip / other to retain the lamp.

EDIT : You are single storey too, so no need for fire rated fittings so much more choice  

[Dreadnaught]

2 minutes ago, Nickfromwales said:

I personally prefer the led flat panel ( 180mm round ) LED types nowadays, and the light is just spectacularly better than a single small spot

 

Interesting. Even in a living room? I had thought such lights were only for kitchens or bathrooms: more utilitarian spaces needing bland flood lighting.

[Jeremy Harris]

3 minutes ago, Nickfromwales said:

Different types of downlights can have much shallower depths

I personally prefer the led flat panel ( 180mm round ) LED types nowadays, and the light is just spectacularly better than a single small spot. There are instances where I will still fit a 'regular spotlight' but they need to be a nice looking fitting with no horrible visible clip / other to retain the lamp.

EDIT : You are single storey too, so no need for fire rated fittings so much more choice  

 

 

Exactly what I've done in our kitchen, replaced deep downlighters with very slim LED panel lights.  The panel lights aren't much thicker than the plasterboard and give off a much brighter and more pleasantly diffused light.

[lizzie]

14 minutes ago, Dreadnaught said:

 

@lizzie thanks. Can I just check that it is 400mm of blown-cellulose insulation in your roof? Did they come along with the blowing machine and cut disks into your ceiling to blow it in? Its not some sort of cellulose batt that they used?

 

It does seem a bit odd to me that they would go through palaver of bringing the cellulose blower to site just for the roof.

 

Good point about the ceiling service-void and downlighter. I must remember to watch out for that.

 

 

Yes the blown insulation...blower machine is just a van probably size of a transit....its self contained and portable, all runs from the van. The insulation is delivered separately and for me it was a massive pile of bags.  They feed the bags into a chute and it pumps the insulation up through holes they cut at various points in the vapour barrier they then tape the holes when finished.

[Dreadnaught]

5 minutes ago, Nickfromwales said:

You are single storey too, so no need for fire rated fittings so much more choice 

 

Oh I clearly have so much more to learn about. I had not realised that.

[Nickfromwales]

4 hours ago, Dreadnaught said:

 

Interesting. Even in a living room? I had thought such lights were only for kitchens or bathrooms: more utilitarian spaces needing bland flood lighting.

Not necessarily in the living room, but as an alternative for areas you'd consider fitting a 'regular spotlight'.

[lizzie]

6 minutes ago, Nickfromwales said:

Different types of downlights can have much shallower depths

I personally prefer the led flat panel ( 180mm round ) LED types nowadays, and the light is just spectacularly better than a single small spot. There are instances where I will still fit a 'regular spotlight' but they need to be a nice looking fitting with no horrible visible clip / other to retain the lamp.

EDIT : You are single storey too, so no need for fire rated fittings so much more choice  

Mine are tiny little led and needed more depth than MBC service void ...no-one notice the service void spec was so small for the ceiling.  I  am single storey too. If you know before hand you can get MBC to increase it but we did not so we were stuck with it and had to rectify as best we could. Lighting was already specced and everyone had had the drawings well in advance.....

[Nickfromwales]

2 minutes ago, Dreadnaught said:

 

Oh I clearly have so much more to learn about. I had not realised that.

Fire rated is only applicable if there is a 'deemed habitable' room above. You're 100% off the hook there.  

[lizzie]

@DreadnaughtThe other thing to be aware of on the ceiling service void that the vcl membrane can pillow when filled with insulation and so you need to make sure its not pillowing down into the service void where your lights will sit......yes we had that too and had to make little wedges to prop it up and keep it clear.....

 

Of course all of this is of no consequence to those with pitched roofs and loft spaces it is only relevant for flat roof or vaulted ceilings.

[Dreadnaught]

6 minutes ago, lizzie said:

The other thing to be aware of on the ceiling service void that the vcl membrane can pillow when filled with insulation and so you need to make sure its not pillowing down into the service void where your lights will sit.

 

Ah, makes sense. I will have vaulted ceilings throughout so highly relevant. Thank you.

[Gone West]

13 hours ago, lizzie said:

My house is very quiet and well soundproofed, we hear no external noise.....I do have very good triple glazed windows.

Yes I agree that triple glazed windows have a far greater effect at reducing sound than the type of insulation. We have good airtightness as well, which I think is another reason our house is so quiet.

[Dreadnaught]

1 hour ago, PeterStarck said:

Yes I agree that triple glazed windows have a far greater effect at reducing sound than the type of insulation. We have good airtightness as well, which I think is another reason our house is so quiet.

 

Yes. Your and @lizzie's comments both support my hunch on where best to spend limited funds to maximise sound proofing. Funds are best spent on a triple-glazing upgrade and airtightness and not on replacing Earthwool/PIR with blown-cellulose in a (thicker) double-stud wall.

 

But its only a hunch; I don't know how to support this guess with calculations.

[lizzie]

@Dreadnaught we chose this wall system for practicality with access as the private drive that leads down to us is narrow (bin lorries dont come down) and lined by historic tpo’d  yew trees.........we would never have got the bigger panels down. Some Tf companies were quoting us to crane panels off up the lane and bring them down one by one which would have been a real headache.  In the event even though we chose the system that was easier to get on site the eps for slab came on a massive vehicle from Ireland.  It had to go to nearby garden centre to be unloaded and then contents brought to site in smaller vehicles...

 

I used good quality plasterboard which also helps with soundproofing.  Our house is warm, comfortable and quiet. I have no regrets about choosing this wall system over the twin wall system.

 

If you have an eye on sale in the future no estate agent is going to quote decrement delay in the sales particulars but the upgrade from double to triple glazing will be a big plus for a buyer.

[Dreadnaught]

5 minutes ago, lizzie said:

If you have an eye on sale in the future no estate agent is going to quote decrement delay in the sales particulars but the upgrade from double to triple glazing will be a big plus for a buyer.

 

Thank you @lizzie. Good point. Your comments are very helpful.

 

6 minutes ago, lizzie said:

I used good quality plasterboard which also helps with soundproofing.  

 

That would be Gyproc Habito I believe. Certainly superior but, as I understand, sometimes cursed by installers?

[lizzie]

2 minutes ago, Dreadnaught said:

 

Thank you @lizzie. Good point. Your comments are very helpful.

 

 

That would be Gyproc Habito I believe. Certainly superior but, as I understand, sometimes cursed by installers?

Nail on head....installers who think they are too smart to follow the instructions!  If (and when) they do install as recommended then its not a problem.

 

btw its great I can hang anything anywhere and walls feel really solid too. 

[Dreadnaught]

@lizzie did you use Habito everywhere? What about ceilings? And, for example, in the utility room? What about bathrooms, don't they need moisture resistant board?

[lizzie]

Just now, Dreadnaught said:

@lizzie did you use Habito everywhere? What about ceilings? And, for example, in the utility room? What about bathrooms, don't they need moisture resistant board?

Ceilings are standard board, bathrooms are moisture resist and the special waterproof board in wet areas.  Our bathrooms are fully tiled.

 

Utility yes habito the same.

 

We had nearly a pallet of habito left over so I have a very smart garage with walls boarded out in habito LOL..ok for hanging shelves in time I guess!

[Russell griffiths]

Have you considered using an i joist for the walls and getting it stick built on site, 

no crane no forklift, 2 chippies and a good set of drawings 

 

[Dreadnaught]

23 minutes ago, Russell griffiths said:

Have you considered using an i joist for the walls and getting it stick built on site, 

 no crane no forklift, 2 chippies and a good set of drawings

 

 @Russell griffiths, good question. No I hadn't. I started by assuming that I would go for an MBC-style factory-built frame. Its only when I received their details and quote did I first think about deviating from the standard passive double-stud wall. Open stud is new territory for me.

 

The advantages of going with someone like MBC are that its quick to get to weathertight compared to a stick build. And they do the foundations too, giving the impression of reducing the build riskiness. And companies like MBC also give the impression of easing the path, providing reassurance, being easier for a novice like me. I can easily appreciate that for someone with your level of experience and ability that a stick build would be attractive (I suspect you'd do the build yourself). I am much more wary as a beginner but possibly without good reason. I suppose it depends on whether I could identify a pair of chippies I truly trusted, no easy task as I am already finding that trust-filled relationships can be few-and-far-between in self build. I have already had the impression from some parties that I am viewed as a meal-ticket-on-a-plate.

 

Having said all of this, I intend to devote plenty of time to being on site. And I am also keen to be as involved as much realistically possible given my total inexperience. 

 

Hmm, food for thought. Thanks for the comment.

Edited January 6, 2019 by Dreadnaught

[Dreadnaught]

Building on your comment further, @Russell griffiths, I think I am lucky to have chosen a good architect. She is a certified passive-house designer and is experienced with designing timber frames (she has, at various times, even been retained by frame companies to do their designs). And I feel I have excellent working relationship with her. The only disadvantage in choosing her is that she is not at all local, she lives many hours away from my site. And she not overly keen on wielding spreadsheets for some of the more detailed building physics work.

 

My choice of architect has presented me with a puzzle to solve about how I should structure my build team. I could do with somebody local (to Cambridgeshire) to compensate for my total inexperience, to have a rolodex of local contractors (and mental list of ones to avoid), to attend weekly onsite meetings and advise on quality, sequencing, and resolving problems. It would seem to be that that person would be an experienced old hand but ideally someone who appreciated the importance of airtightness, etc. Is this a good idea?

 

It did cross my mind that I could all but rely on BuildHub (BH) to act as this party. BH has been hugely valuable to me thus far. But am I being unrealistic. 

 

I would welcome others views on this.

 

As some others have said (was it @recoveringacademic?) I am huge fan of building empowered teams filled with trust, but given me short (and no doubt unrepresentative) experience thus far in self building that does not seem to be usual culture. Or am I wrong?

 

Its a hugely steep learning curve (which I am secretly rather enjoying).

Edited January 6, 2019 by Dreadnaught

[Gone West]

1 hour ago, Dreadnaught said:

Open stud is new territory for me.

 

If considering I-beam construction did you look at Touchwood Homes?