Home Forums General Discussion What is the best way to insulate walls without removing the wall panels? Reply To: What is the best way to insulate walls without removing the wall panels?


Sorry Norman, I am not trying to contradict every single comment you post but I need to clarify something else. I would like to add to Vicki’s comments.

I work as Eco Design Advisor within Building Services at Palmerston North City Council. Wall insulation with foams or other ‘similar’ products are far from being considered exempt from Builing Consent in Palmerston North at this stage.

Examples of NZBC compliance issues that arise when insulating exterior walls and what Clauses they relate to are:
B1 – Structure: bracing for example. This can also happen when lining of interior walls is affected.
B2 – Durability: moisture could cause rot to the framing. Also, certain foams will damage certain types of electrical wiring and cause a fire hazard.
E2 – External moisture. Very important, especially as the recommended practice for insulation retrofit is to install building paper if the wall does not have any. Other issues would be waterproofing around window frames, which in a brick veneer wall are known to leak and to rely on air flow to dry
E3 – Internal moisture. If the product releases moisture into the building for some time after its installation
G5 – Interior environment: if the product releases toxic fumes
G9 – Electricity: as per issues with wiring described above
H1 – Energy efficiency: if compliance needs to be demonstrated, for example if a new window or door is installed in an existing wall.

You can download the Building Code Compliance Documents here: http://www.dbh.govt.nz/compliance-documents

This type of technique also puts councils in a difficult situation because building inspectors must be able to inspect construction work in order to determine if it has been done properly. How can they inspect something that is hidden inside a wall?