Yeah, I assume this is the reason trickle vents in windows are in the regs now i.e. new builds whilst very well insulated became too air-tight reducing air quality. I think when retro-fitting an older property there seems to be a lot of conflicting information on what is best (the example in the vid being lime plaster and breathability). Seems to me you've got to look at an overall picture of an individual property to find a good balance point.

@@blairkingsley6440 Actually, older properties can be more airtight than newer properties because they used wet plastering and haven’t engineered everything to costs. The video I found here was very interesting in that respect: kzfaq.info/get/bejne/jMdkpNZ5m9bIdYk.htmlsi=j_1fqkUtN-rzobhA

​@@christianu8023I found this video really interesting. Thank you.

You've raised some fair points and I appreciate the feedback although I'm hesitant when getting into discussions with viewers who have no profile image or display a real name? I hope you don't take this the wrong way, Many on here are out to cause trouble and hide behind an avatar. If you want genuine discussions I suggest disclosing your real name and photo of yourself? I've already had to block one individual today as things quickly turn nasty I'm happy for viewers to ask questions and challenge what I do and say but atleast tell me your name? Anyway back to your comments, by no means is this product as thermally effective as thicker insulation products. it's a thin option for those who either do not want the hassle of rads + fixtures being removed and replaced or are on a budget or do not wish to lose the floor space. The cork layers stop condensation from forming on solid walls by raising the thermal value enough therefore eliminating the issue of black spot mould so for me this product is ideal for treating the issue of condensation and black spot mould and at only 6mm corksol state that this product indeed gives a thermal improvement of 30% the science behind this statement corksol stand behind so better to talk direct to the supplier of the product if you wish to challenge this? You could be right about the patch of lime being covered in paper previously or even a heavy piece of furniture may have been close to the wall who knows I can say I have seen this issue before with lime walls I'm not bashing lime its lovely stuff but I don't think it's a cure for all. Most of the lime plaster in this property actually has already been replaced with gypsum and cement probably in the 60's or 70's I did not suggest anywhere that I am using cork in this job for breathability I simply mentioned in the video that the corksol could be used with a lime skim if breathability is important. Again I'm happy to answer questions but would prefer if people atleast include a real name

How would you achieve a 90% improvement please?

​@ookoro More insulation in the walls, also look at underfloor insulation as well as on the external wall in between floors. The cost can quickly get away from you though and if you do get properly airtight (this kind of solution looks like it provides suitable airtightness as well as insulation) though you really should be thinking of MVHR for ventilation.

@@MichaelHalpenny The issue in the video above is surely that space in that room is at a premium. It's a solid brick wall so the only solution is internal insulation, but the more of that you add, the less space you have in the room.

​@dallan7740 The point about the size of the room is well taken. My comment was about how you might achieve a 90% reduction. This is very much shallow retrofit rather than deep retrofit and you'd need to go deep to get 90%, might need to do windows as well but gets very expensive very quickly. Sometimes this kind of work is the best balance that can be achieved. P.S. It's possible to use external wall insulation on a single leaf building assuming that there are no planning issues. Tends to get expensive though.

@@ookoroThe U-value of a 1 brick solid wall plastered is about 2.2 watts/m2 degreeC. With 7mm cork insulation, U-Value is about 1.7, so 30% better. Wall dry lined with 25mm polystyrene backed plasterbpoard U-value about 0.9 so about 140% better. Current Building regulations for domestic walls is that U-value of walls should be less than 0.3 so 630% better than the existing.

I plan to do my own long-term case study on the cork coatings on a property I own

Yes good shout. A 4mm floor panel overlay will make a difference and decent underlay The primer was a basic PVA mix. No primer is required for skimming over the cork 👍

@@SDRobertsPlastering I’m a plasterer do you get much work doing this domestically or is it more of you do it when the works there because I’ve looked at doing other stuff but it’s always traveling miles or the works intermittent?

Fireplace chimney, is this vent closed or open? What way, does it allow cold moist air to come down the chimney and dampen the walls? Are there any air vents in that room? What is the humidity reading in that room on average?

@@Google_Does_Evil_NowCouple of points here, I have non-functioning fireplace that has been boarded out. I fitted an airvent and when it's open the draught id always into the chimney.

If space available, fittting MVHR in the attic is best for old properties.

Yes the cork is a fantastic acoustic insulator also. It can be left bare it will not flake off. This product can be used externally and has been through rigourous pull tests

If I wanted to spray my walls with this after removing my wallpaper and leave it bare - no skimming after, is this very expensive than having a normal skimming done to smooth out the wall?

Hi, I have a link in my bio you can upload images and information. Costs vary alot job to job with IWI

Painting Zinser on as a primer would be a vapour barrier on the cols side of insulation, so you would get condensation and mould problems again.

@@robertsmart7484 I was thinking that the masonry or cavity is the first insulative material, so it would be fine may be?

@@bikerchrisukk It's a solid wall, so no cavity. But a vapour barrier on the plaster might just be OK, because the thin layer of cork isn't very insulating - it adds a bit less thermal resistance than the 9" brick wall, so a vapour barrier on the plaster may be perhaps 3/8 the way through the overall insulation of the wall, which may be OK.

@@robertsmart7484 That's what I was thinking. If there was 100mm of PIR internally, I'd definitely say VCL should go on warm side, then plasterboard. Mind you, cavity/air gap would be helpful in that situation. Doing a job at moment where existing is 9" external wall external leaf, 1" cavity, 4" stud with full fibreglass infill and then weirdly 2 x half inch plasterboard. I guess they wanted something solid to fix to, but if starting from scratch I do OSB then pboard

No need to hack off unless existing plaster is shot / penetrating damp etc. Remove mould from surface, prime, apply X2 layers of cork then skim straight over once it's fully cured no primers needed 👍

If the wall was back to brick would you then do thicker coats, more coats, or same depth@@SDRobertsPlastering?

@@blairkingsley6440 The product is designed to build up in 2 layers although I have done 3 before this process would take days and a better option would be to install a 22mm thermaline or if breathability is required you could use a breathable backing plaster first (Adaptavate / limelite ) then apply the cork layers then skim 👍 I hope this answers your question

No primers required Ensure surface is clean ,dust free and sound. No primer needed when skimming the cork 👍 If the walls are very old I sometimes apply a weak mix of PVA for belt & braces approach

@@SDRobertsPlastering thanks mate 👍

No such thing as a stupid question in my view. There are indeed cork tiles you can purchase relatively cheap too. You could bond them over existing tiles but then you'd have to cover with another layer of finished floor because I doubt they would be durable enough to withstand the day to day foot traffic etc without breaking down unless you opt for a laminate board that has cork inside two layers of wood flooring

@@SDRobertsPlastering Thank you kind soul for replying, I was going to buy a few cork tiles self adhesive type just out of curiosity, did I see you use a item that can see what the temperature is like a gun thing that you point to the wall ? I don’t know what there are called would like to buy one if they are not too expensive and don’t know which are good or rubbish = like most things in life can get good items and ones that are more landfill, have no idea what the name or brand that is good, I do know my floors and walls are so cold that I was also thinking of getting some cork rolls to see or try different things as you would do with wallpaper, watching your video has given me lots of ideas , so if the don’t work out at least I can blame you = joking = dying is easy comedy is hard , you will need a whiskey just to get through this message, take care kind soul.

I'm interested if it can be used on ceilings also ?

Hi thanks for watching, we cover the whole of Warwickshire if you could please complete our customer job form using the link below please include approx dimensions and a photo upload or short video showing the room we can get a cost estimate sent to you form.123formbuilder.com/2387712/contact-lead-form Thank you Stuart SD Roberts Plastering & Wall insulation

The floor timbers must be ventilated voids should be left clear 👍

It is possible to spray the underside of the floor boards with foam but you need to keep the void properly ventilated

@@hughmarcus1 I suppose you could do. A 10mm XPS panel overlaid before the underlay / wood floor goes down would be very simple to do also

@@SDRobertsPlastering it would. But the problem with rigid board insulation is air movement around it. You’d need to properly seal between the boards & around the edges, probably with expanding foam, which is very messy. The advantage of sprayed foam is that it fills all the gaps & addresses one of the biggest issues with suspended timber floors - air leakage.

If using a breathable system you'd need a breathable skim coat of plaster and breathable paint 👍

It's cork based so no 👍

Which natural internal airflows have I cut off friend?

The imaginary one lol. The guy diddnt watch this video properly and talking nonsense ​@@SDRobertsPlastering

Uncontrolled air flow is not your friend. You did well to point this out and inform that this contributes to lowering the internal surface temperature.