Render on board fixed to timber frame or should we build a blockwork outer leaf?

[overthehill]

Hi, 

 

We are building a timber and oak frame house, outside will be a mix of render and timber cladding. On the render bits should we use renderboard fixed directly to the kit as opposed to render on a blockwork outer leaf? What are the advantages and disadvantages of both methods? Is there a big cost difference?  Any thoughts advice appreciated.

[G and J]

We're hoping to start our timber frame build in the next couple of months, also combination of render/timber cladding.

 

We started by thinking we would not use block work, however on investigation some lenders (standard and lifetime) have specific guidelines as to what they will or will not lend on.

 

It's not our intention to sell, and we are not looking to borrow, but it's a case of never say never, so we have decided to block under the render and cement board under the cladding, which was also reduced. The sweet spot on current "rules" appeared to be min 50% masonry and max 50% timber cladding (even if on blockwork). There are no doubt specialist lenders, but if the worst happened we'd rather things be as straight forward as possible. For same reason we will take a build warranty, even if the liklihood a ever successfully making a claim is slim.

 

It turns out that there is not much additional m2 cost and in the end we probably will have slightly better acoustic performance, albeit with a thicker wall, which for us is a factor as we have a very narrow site. 

[nod]

A masonary outer leaf is definitely better than fully timber frame 

Much more solid But render on a cement board or block are both fine 

[overthehill]

ok thank you, Im leaning towards block work as you say nod it must be more solid at least thats my impression, Ive also read about board render cracking not sure if this is true or not but the mortgage point is good to note. Good luck with your build @G and J hope it goes smoothly : )