Inserting an Extra Floor in a Double Height Space?

[Ferdinand]

Scenario: if I construct a 1.5 storey house with a galleried living / dining space, which construction method makes it most straightforward to insert an extra studio or bedroom when I want to sell, and what is involved?

 

I can say more, but I would like to have a range of answers on likely problems on this one, as I am just musing.

 

Ferdinand

Edited January 18, 2017 by Ferdinand

[Onoff]

How about exposed "rafters" as part of the build which then become the floor joists later on?

[ProDave]

This does not sound to dissimilar to what we are doing.  Upstairs is a warm roof with vaulted ceilings.  In one (daughters) bedrom it is being kept open as a full height space, then with a mezanine floor above the small bedroom.  Our own bedroom has a higher than normal ceiling height of about 2.8 metres so is then closed off to give us some loft space, while the area above the landing and bathroom has a normal 2.4 metre ceiling and a larger loft space you can almost stand up in.

 

So translating this to your scenareo, I think you are meaning a double height space that you can later put a floor in to create an upstairs?  Just make sure you build in something substantial to fix joists to when you are ready.
 

[PeterW]

Leave a series of slots in the internal block work for the joists and then either fill them with foam blocks or just board straight over. 

 

Then just cut them out at a later date and insert the joists - leaving a 100mm gap in one cavity to push the joist into to get them into the walls. 

[Nick]

19 minutes ago, PeterW said:

Leave a series of slots in the internal block work for the joists and then either fill them with foam blocks or just board straight over. 

 

Then just cut them out at a later date and insert the joists - leaving a 100mm gap in one cavity to push the joist into to get them into the walls. 

 

Also could go the the less neat but easier to retrofit way of fitting the joist hangers ready to go and then just boxing around them for now.

[PeterW]

5 minutes ago, Nick said:

 

Also could go the the less neat but easier to retrofit way of fitting the joist hangers ready to go and then just boxing around them for now.

 

Make a feature "shelf" on the walls and fit uplighters into it..??

[Nick]

4 minutes ago, PeterW said:

 

Make a feature "shelf" on the walls and fit uplighters into it..??

 

Are yeah... I've built a few "features" in my time

[Ferdinand]

Thanks.

 

The intention I am thinking about is to allow flexibility later.

 

One of my inspirations as to the form was the Grand Design known as the "Modest Home" (modest for Grand Designs - 1500 sqft build budget 200k iirc), Hoo House in Woodbridge, which is part 1.5 storey and substantially 

 

http://www.eadt.co.uk/news/visionary_family_home_a_work_of_love_1_658404

 

http://www.channel4.com/programmes/grand-designs/on-demand/46761-019

 

Ferdinand

 

 

 

[Ferdinand]

Thanks for the comments so far.

 

So .. supplementaries :-).

 

8 hours ago, PeterW said:

Leave a series of slots in the internal block work for the joists and then either fill them with foam blocks or just board straight over. 

 

Then just cut them out at a later date and insert the joists - leaving a 100mm gap in one cavity to push the joist into to get them into the walls. 

 

I can see that that would work. That implies internal blockwork and a 'cavity' type structure - or a rainscreen (eg cladding or render over insulation) or similar on the the outside so that the joist ends do not protrude too far towards the outer surface, which may not be ideal (cold bridges, rotting). I expect that can be detailed appropriately with ease.

 

8 hours ago, Nick said:

 

Also could go the the less neat but easier to retrofit way of fitting the joist hangers ready to go and then just boxing around them for now.

 

Joist hangers :-). I have been looking into this a little. As far as I can see from a cursory survey of what is on sale, joist hangers for blockwork require to be inserted into the blockwork itself, while those for timber seem to be attachable to the surface.

 

For a conservatory roof where access was required for maintenance I dealt with this by putting a chunky - perhaps 8"x4" wall plate on the blockwork with appropriate bolts then mini joist hangers on the wall plate to support the roof.

 

But are there surface attachable joist hangers for use with blockwork? (Though I guess that the blockwork itself could be slotted if necessary).

 

8 hours ago, PeterW said:

 

Make a feature "shelf" on the walls and fit uplighters into it..??

 

11 hours ago, ProDave said:

This does not sound to dissimilar to what we are doing.  Upstairs is a warm roof with vaulted ceilings.  In one (daughters) bedrom it is being kept open as a full height space, then with a mezanine floor above the small bedroom.  Our own bedroom has a higher than normal ceiling height of about 2.8 metres so is then closed off to give us some loft space, while the area above the landing and bathroom has a normal 2.4 metre ceiling and a larger loft space you can almost stand up in.

 

So translating this to your scenareo, I think you are meaning a double height space that you can later put a floor in to create an upstairs?  Just make sure you build in something substantial to fix joists to when you are ready.
 

 

That is an attractive idea. I had mused about if eg ordering a timber frame from MBC and having the floor cassettes for the future inserted floor supplied initially, which could simply then be added in with a block and tackle from the Ridge Beam at some point in the future. The geometry would work.

 

11 hours ago, Onoff said:

How about exposed "rafters" as part of the build which then become the floor joists later on?

 

I like exposed tie beams especially as they age, but the numbers vs span vs spacing would have to be thought about carefully to look OK now and meet any likely spec for the future.

 

Type of Blockwork

 

Is there much of a constraint on types of blockwork which can support joists for an upstairs eg I am limited to higher density blocks rather than some of the lighter ones that we can use for walls ?

 

Timber Frame

 

Are there any problems doing this with timber frame? I expect not provided that a conversation is had with the designer.

 

Cheers

 

Ferdinand

[ProDave]

What I was getting at with TF was at your proposed future floor height, build in a horizontal ring beam of 8 by 2 timber. That can be plasterboarded over for now as it would be flush with the wall.  Later on, cut away the plasterboard and fit the floor on joist hangers fitted to this horizontal 8 by 2.