Jul 19, 2019 7:44 am
Hi all,Could you please let me know a way to check whether the builder has upgraded the insulation as required by us.So far what I can see is a silver colour insulation wrap around the house and just below the roof. Is there anything extra they should add.We upgraded walls to 2.5 and ceiling to 5.
Jul 19, 2019 9:19 am
So far what I can see is a silver colour insulation wrap around the house and just below the roof. Is there anything extra they should add.We upgraded walls to 2.5 and ceiling to 5.
I reckon after upgrading our own insulation in our current build, and installing some of it ourselves I am now qualified to try to answer this one....The wall wrap you see is likely just a basic foil backed (likely non-breathable) product that offers little actual insulation benefit but does certainly assist with reflecting heat coming in from the outside in summer. It will also help with reducing air movement (leakage) through your building envelope. So that is a good thing, but this is not technically 'insulation'. Having said that there is a slight chance it is a higher spec product, but as I said this looks like a fairly standard foil type builders wrap.
** Side note....Since May 1, 2019 I am pretty sure all new buildings in Australia now have to install a 'breathable' type wall wrap in certain climate zones. So google climate zones and find out where you are and if your builder has installed the correct type of wall wrap according to the new building code. A breathable wrap allows water molecules (as vapour) to move through the wrap so your cavities can dry out. Particularly useful in colder areas where the internal temps are much warmer than external during those winter months.
Anyhow for your actual wall insulation, R2.5 will typically be a high density wall batt. I am assuming it will be 90mm thick and so will essentially fill your entire wall cavities. Here is a picture of our R2.5 batts getting installed into all of our walls, including internal. ** You may only have your external walls getting insulated, as it is not compulsory for builders to add these to internal walls. We paid a couple of $$grand extra for this. One thing to check is the walls between your garage and internal rooms should also have insulation.
The important to check with wall insulation is that there are no gaps. Supposedly even 5-10% gaps can result in up to 50% less efficiency of the insulation. So your R2.5 could easily perform like an R1.5 if it isn't installed correctly.
The best way to find out what product they are using is to either see the bags onsite prior to installing (the R rating is printed on the bag) or check your skip soon after installation! Yay, we all love going through our skip bins!
If you are also getting 'batt's here (we actually have a combination of batts on the outside perimeter and then 'blown-in' cellulose or 'loose-fill' going above our ceiling plasterboard just before handover) the builder will either install them before your ceiling plasterboard goes up or possibly afterwards?. Typically they will install the ceiling batts prior to plaster, but only if they use additional battens to attach the plasterboard to. If they do it later they will usually throw the bags into the roof area earlier on though.
To find out what actual batt R-rating they are using again if you can spot the bags it will be printed on them. But if you find out what brand they use, go to their website and each R rated batt for ceilings will have a specific thickness. For example Knauf R4.0 batts are around 210mm thick from memory.
Here is a pic of someone installing ceiling batts after plaster has been installed. Be careful if your builder uses this method as I have personally seen some very poor installs done this way. I feel it is because the installer doesn't believe the owner or builder will ever actually check their work?!
Anyhow it's good to ask this question early so they don't cover up your walls and ceiling and forget to install the correct the products. It also allows you to closely monitor how it is installed so you get the actual performance rating of the products you have paid for. Remember no gaps is the key, and also the batts should not be compressed and be kept dry at all time....this is also important.
One final thing to check before hand-over is that the insulation installed (or anyone else working in the roof area) haven't damaged your heating/cooling ducts if you have any. I have heard stories where insulation installers have cracked it with all the ducts hanging everywhere and simply cut the hanging strings!
Good luck with your build!
Check our Homeone build blog here
Jul 19, 2019 9:33 am
Just found a photo of what our wall insulation bags look like:
You can see with 'Knauf' brand, the R-rating and dimensions (see the '90 x 430 x 1160mm' down low) are printed on the bags.
Check our Homeone build blog here
Jul 19, 2019 10:42 am
Wow amazing detailed reply darb74 .Thank you so much for your time and effort on that..Really appreciate it..
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