Can someone clarify Part E?

[Ben Weston]

Hi all,

 

We're doing a significant renovation of an 1870s cottage, including a two-storey extension that over doubles the floor area. I've only recently become aware of Part E. It hasn't been mentioned by our architect or BC.

 

In terms of the actual construction, stud walls have been made out of 2x4 and will be packed with rockwool insulation and boarded with regular 12.5mm plasterboard. Is this enough? The first floor deck sits on Posi-Joists and we were going to pack this with as much fluffy as we can fit in there (about 200mm). I'm concerned this won't be enough.

 

The main wall between the cottage and the new extension is a typical solid wall construction which will be rendered in lime both sides. Nothing more will be added to it; is this enough?!

 

Hoping someone can clarify Part E and how it relates to what we're doing.

[Mr Punter]

Part E will mostly not be relevant as this is an existing house.  It has most impact for new build flats and houses where there are party walls and floors .

[saveasteading]

Only from memory:

 

Isn't part E about new build, not refurbs?

You should upgrade as far as reasonable but you aren't looking for new build standards.

 

I suggest you have 2 options. 1. Leave it to your consultants. 2. Read through part E yourself.

 

It is online and free to download.

 

The green section near the start is 'the standards' and this will clarify the principles  on whether and how it applies to your circumstances.

The greater bulk that comes after is mostly explanatory and suggestions.

 

When I need serious analysis of regulations, I print off the relevant bits and mark up the clauses that apply. I'm sure this can be done on screen instead, just not by me.

[kandgmitchell]

Have a look at page 8 of the Approved Document to Part E, in particular E2. It'll be applicable to new floors and walls being constructed not existing. Note also the exemptions to the right side for particular walls.

 

You need an airbourne sound resistance of 40db for your new internal walls. Looking at Knauf's details their 12.5mm wallboard with 97 metal studs and 25mm insulation gives 42dB. Your studwork will be at least as good as that. There's no requirement for testing anyway. The masonry wall will well exceed the requirements.