Concrete/rebar....Can I offset vertically between floors?

[cheeryble]

We have a rai......it's a small hilltop with spectacular views.

My land has a natural"driveway" down one side...it drops about 2metres below the main top level.

You can see it on the first pic on which of course the drop is much more neat and schematic than real life but tells the story OK.

I'm building a small chalet and thought we'd use this difference in levels to our advantage.

Basically thinking I can use the balcony (which may become the whole length of the house) as a roof for a store-room/bedroom/garage below.

I would rather only come out 2.4m with the balcony, it's big enough.

However to maximize the underneath room/s I have on the drawing offset the inner legs so that although the roof is 2.4m the inside can be 3m.....or maybe more.

Obviously I have to cut back the dirt to a reasonable angle and maybe channel water away from the downstairs wall.

Any problems or considerations or brainwaves here?

Yes i know I've got to shift the balcony roof along I did a quick change from it being on the end this is pretty rough so far....get it figured then iw ill draw properly

ps already thought a car actually doesn't need a garage that could just be a lightweight roof extending out......better use solid rooms for better purposes.

Edited January 19, 2015 by cheeryble

[IMHO]

This is very doable, but in a slightly different way to what you're thinking.

Looking at the side elevation (pic #1), the middle post would actually run inline with the footing post below (not offset at all) - i.e. creating an overhanging beam supporting the front wall. The tricky part is that balcony - where it terminates to the house it would currently be mid-beam, and that's a problem. The solution to that is simple though - just make it the same width as the house

The end result would be, front to back you have 3 rows of 3 posts, but with 4 lateral beams (one extra to support the front wall of the house).

Option #2 is, from left-to-right (looking at the front elevation), just run 6 posts (2 wide, 3 deep) at the same width as the balcony - the result here is that the whole house overhangs the posts on both sides - that's also doable. Overhangs up to 1.5M are very typical in Thai construction.

Either way, you'll need an engineer to design the beams, that's for sure.

Can you give us some basic dimensions? It's possible option #2 could actually save you money too (by deleting 3 posts) - it all depends on how wide the house needs to be.

Edited January 19, 2015 by IMHO

[trogers]

Obviously I have to cut back the dirt to a reasonable angle and maybe channel water away from the downstairs wall.

I would be more worried over slope stability. A natural slope would be 42^o measured from the foot of the slope upwards.. In order to park a car, you need to cut a steep slope with a 3.2m overhang (+0.8m cantilever balcony roof).

This would mean a slope of over 60^o.

[cheeryble]

This is very doable, but in a slightly different way to what you're thinking.

Looking at the side elevation (pic #1), the middle post would actually run inline with the footing post below (not offset at all) - i.e. creating an overhanging beam supporting the front wall. The tricky part is that balcony - where it terminates to the house it would currently be mid-beam, and that's a problem. The solution to that is simple though - just make it the same width as the house

The end result would be, front to back you have 3 rows of 3 posts, but with 4 lateral beams (one extra to support the front wall of the house).

Option #2 is, from left-to-right (looking at the front elevation), just run 6 posts (2 wide, 3 deep) at the same width as the balcony - the result here is that the whole house overhangs the posts on both sides - that's also doable. Overhangs up to 1.5M are very typical in Thai construction.

Either way, you'll need an engineer to design the beams, that's for sure.

Can you give us some basic dimensions? It's possible option #2 could actually save you money too (by deleting 3 posts) - it all depends on how wide the house needs to be.

Thanks IMHO

we may need to define terms like "front" anyway I'll try and digest this in the morning and may get back to you Brain vegetating tonight probably perfectly cogent just me.

Oh your measurements:

The main building is one room including modest shower room total 7.5m x 4m.

Balcony 2.4m deep I think's enough and at least 4m long though may be up to 7.5

Edited January 19, 2015 by cheeryble

[cheeryble]

Obviously I have to cut back the dirt to a reasonable angle and maybe channel water away from the downstairs wall.

I would be more worried over slope stability. A natural slope would be 42^o measured from the foot of the slope upwards.. In order to park a car, you need to cut a steep slope with a 3.2m overhang (+0.8m cantilever balcony roof).

This would mean a slope of over 60^o.

Thanks for concern!

I've noticed that in this area same dirt which has been cut away for tracks etc stands perfectly well at a very steep angle maybe 80 degrees from horizontal.

In fact a macro has been at work on a site and they've been a wee bit more conservative (but not much) at about 60 degrees.

I see that in the few places where there have been little slides (not on my land) it doesn't go back to a shallow angle but stays nearer maybe 70 or so.

You may also remember that one side of my land is no less than a cliff (the neighbouring land was cut out for fill a couple decades ago and the proceeds went to build the church) and it's between 80 and 90 degrees no less.

There is a backup too to build a proper retaining wall with rebar....but I don't think it's going to be necessary.

As I'm using thermalite blocks I see the lower floor (just a modest room after all) as not needing supporting beams perhaps just a strip foundation, concrete base, and blocks. Chance for economy.

Edited January 19, 2015 by cheeryble

[IMHO]

This is very doable, but in a slightly different way to what you're thinking.

Looking at the side elevation (pic #1), the middle post would actually run inline with the footing post below (not offset at all) - i.e. creating an overhanging beam supporting the front wall. The tricky part is that balcony - where it terminates to the house it would currently be mid-beam, and that's a problem. The solution to that is simple though - just make it the same width as the house

The end result would be, front to back you have 3 rows of 3 posts, but with 4 lateral beams (one extra to support the front wall of the house).

Option #2 is, from left-to-right (looking at the front elevation), just run 6 posts (2 wide, 3 deep) at the same width as the balcony - the result here is that the whole house overhangs the posts on both sides - that's also doable. Overhangs up to 1.5M are very typical in Thai construction.

Either way, you'll need an engineer to design the beams, that's for sure.

Can you give us some basic dimensions? It's possible option #2 could actually save you money too (by deleting 3 posts) - it all depends on how wide the house needs to be.

Thanks IMHO

we may need to define terms like "front" anyway I'll try and digest this in the morning and may get back to you Brain vegetating tonight probably perfectly cogent just me.

Oh your measurements:

The main building is one room including modest shower room total 7.5m x 4m.

Balcony 2.4m deep I think's enough and at least 4m long though may be up to 7.5

Here's How I'm imagining the basic posts & beams for my option 1:

The additional beam you see is to support the front wall of the house.

And here's option 2:

The second one is much closer to your original design, and means you would not have a post in the middle of the room to deal with. In order for this to achieve 7.5M total width, either the centre span has to break conventions (4.5M vs 4.0M standard) or the overhangs do (1.75M each vs 1.5 standard) - but an engineer will be able to make it work. Note that if the bathroom will be located on either of those overhangs, it's highly probable it can't be an overhang anymore - i.e. 2 more posts would likely need to be added to that side.

Note: neither of these are to exact size, and neither show the additional beams you'd need to support any internal walls.

Edited January 20, 2015 by IMHO

[cheeryble]

Thanks for taking the trouble IMHO

So your front wall is the wall to the balcony! (Mine was the other side as I wanted a "front" door to be welcoming from the main flattish area of the land.)

Let's call your wall the balcony wall.

Err wouldn't for instance the most central post be sticking up in middle....well not the middle but a couple or three feet INSIDE the room?

On thinking you need to see the inside otherwise you don't know that.

As you can see it's vey simple like a studio apartment.

[IMHO]

Thanks for taking the trouble IMHO

So your front wall is the wall to the balcony! (Mine was the other side as I wanted a "front" door to be welcoming from the main flattish area of the land.)

Let's call your wall the balcony wall.

Err wouldn't for instance the most central post be sticking up in middle....well not the middle but a couple or three feet INSIDE the room?

On thinking you need to see the inside otherwise you don't know that.

As you can see it's vey simple like a studio apartment.

chalet plan view.jpg

Yes, option #1 would indeed have a post inside..

Your plan becomes doable if the space between the posts under the balcony is the same width as the balcony though, or if you use a 7.5M span steel beam to support the roof, and delete the middle post upstairs, like this:

Imagine that new addition is a truss style beam, like this though:

We routinely do beams like this anywhere from 7M to 9M wide, to support the several tons of tile roof on 2-3 car carports, so no reason it won't work for you.

I do have to say this is starting to become a complex build though... if you were to just make the balcony 3M deep, you'd have the space to park a car, and wouldn't need to go to these types of extremes/expenses.

Edited January 20, 2015 by IMHO

[RKASA]

Dig out a space for the building in the hill side - back fill three sides downstairs after treating the outside walls downstairs and have a day light basement into the car port below. Common building practice - nothing really special required as it is just a two story building with entry level on both levels the roof of the carport is just a deck or can be more home space our choice. If you make home space down stairs you can get the same amount of living space with half the roof and foundation of the same size home.

[cheeryble]

Thanks for all contributions....been a bit sick but getting back to thinking this one out.

How i'm thinking is I want to make the minimum spend for the moment and get the one roomer up......but make it so that further add-ons would be easy and probably with just lightweight blocks built on trench foundations for them.

As RKASA says this would be easy enough for the under-balcony area.

A friend just gave me an idea I kinda like.

He said build an altogether smaller main roof maybe JUST overhanging the main room walls.....then go much further out with "wing" roofs.

Or at least start with one of them....A in the pic.....and if you decide you would like to add a room the other side (not the whole length but leaving a space for the entry door etc)

you just attach it on (maybe having made connection available ready to go.

the angle of slope of the sheet roof is an issue. This "B" room could actually be built with simple trench foundation and could drop down nearer ground level to make more slope available.

Thoughts?

Also questions:

I want to keep the A roof at least 2m above balcony if poss for good view.......what's the shallowest angle one can build a sheet roof (probably lined with foil should help waterproofing.)

RElevant to this is although i like Dutch Gable roof maybe I should aljust the type of roof so the A and B roofs can come off the main roof slopes a little higher to give slope to A and B. I think this isn't possible with a Dutch Gable.

IF you've still got brain energy:

Thinking of going up into a cathedral ceiling.

1 Do I need anything across the room to strap the sides together?

2 Do I need a window up there or will it look a bit dark above?

Relevant to the light inside I'm considering large off white rectified tiles 60 x 60.

Are they too cold or will heater do the trick when it's needed?

Thanks

[cheeryble]

Thanks for all contributions....been a bit sick but getting back to thinking this one out.

How i'm thinking is I want to make the minimum spend for the moment and get the one roomer up......but make it so that further add-ons would be easy and probably with just lightweight blocks built on trench foundations for them.

As RKASA says this would be easy enough for the under-balcony area.

A friend just gave me an idea I kinda like.

He said build an altogether smaller main roof maybe JUST overhanging the main room walls.....then go much further out with "wing" roofs.

Or at least start with one of them....A in the pic.....and if you decide you would like to add a room the other side (not the whole length but leaving a space for the entry door etc)

you just attach it on (maybe having made connection available ready to go.

the angle of slope of the sheet roof is an issue. This "B" room could actually be built with simple trench foundation and could drop down nearer ground level to make more slope available.

Thoughts?

Also questions:

I want to keep the A roof at least 2m above balcony if poss for good view.......what's the shallowest angle one can build a sheet roof (probably lined with foil should help waterproofing.)

RElevant to this is although i like Dutch Gable roof maybe I should aljust the type of roof so the A and B roofs can come off the main roof slopes a little higher to give slope to A and B. I think this isn't possible with a Dutch Gable.

IF you've still got brain energy:

Thinking of going up into a cathedral ceiling.

1 Do I need anything across the room to strap the sides together?

2 Do I need a window up there or will it look a bit dark above?

Relevant to the light inside I'm considering large off white rectified tiles 60 x 60.

Are they too cold or will heater do the trick when it's needed?

Thanks

[IMHO]

What is that wall height in the main house? (3M?)

What is the overhang of the the main roof? (1M? 1.5M?)

What pitch is the main roof? (25/30/35 degrees?)

Good to see you have now simplified it by making the balcony wider - have you also considered hollowing out the space beneath the main room - i.e. brick in the 3 walls of it on the "dirt" sides, making another full-size area beneath it?

As for your questions:

1) Most likely, yes, you will need at least one exposed metal beam, with a support in the middle to hold up the centre of the roof for a hip roof, two of them for a dutch hip. An engineer *might* be able to design something that works around this, using a concrete + rebar ring beam on top of the walls though... I'm not an engineer though

2) Depends how bright you want it to be You could either do a dormer, a skylight, or nothing... A dormer will need support though, so it would need to be smaller rather than larger in order to keep from adding more beams into the room.

Edited January 29, 2015 by IMHO

[cheeryble]

What is that wall height in the main house? (3M?)

What is the overhang of the the main roof? (1M? 1.5M?)

What pitch is the main roof? (25/30/35 degrees?)

Good to see you have now simplified it by making the balcony wider - have you also considered hollowing out the space beneath the main room - i.e. brick in the 3 walls of it on the "dirt" sides, making another full-size area beneath it?

As for your questions:

1) Most likely, yes, you will need at least one exposed metal beam, with a support in the middle to hold up the centre of the roof for a hip roof, two of them for a dutch hip. An engineer *might* be able to design something that works around this, using a concrete + rebar ring beam on top of the walls though... I'm not an engineer though

2) Depends how bright you want it to be You could either do a dormer, a skylight, or nothing... A dormer will need support though, so it would need to be smaller rather than larger in order to keep from adding more beams into the room.

Hi IMHO

What is that wall height in the main house? (3M?)

I've been thinking standard.....2.4m

What is the overhang of the the main roof? (1M? 1.5M?)

Was going to be 1m or so until the idea about the "wing" roofs.

The rationale is that with the "wings" one can keep the roof size smaller.

If i have a cathedral ceiling it sometimes the room gets out of proportion height wise......the lower roof would help that.

What pitch is the main roof? (25/30/35 degrees?)

I've been thinking just "normal" which I'd guess is 35 or more?

However that is only because it looked OK sketch-up-ing it.

have you also considered hollowing out the space beneath the main room - i.e. brick in the 3 walls of it on the "dirt" sides, making another full-size area beneath it?

No only the area under the balcony.

I guess it;s a thought.

What i like about the possible "wings" is it makes the building "add-onable" and the extra rooms easily available are either already roofed as under the balcony or a simple lean to structure as on the B side.

​I'm going to experiment with another roof than Dutch Gable as the latter limits (as far as I can see) the pitch of the wings to very shallow indeed.

If it was a simple roof extending over the ends one could run the wings off it higher up.