Extension plans - decision time

[oldkettle]

Hi,

 

We've been working with an architect towards planning application for our bungalow to a house conversion. Due to the way we are charged (no complaint, just a statement of facts) it turned out cheaper for me to play with options myself before the architect puts it all into an application - so sorry the drawings are not perfect :-) No windows shown. They will all be at the front and back only upstairs - the only side windows will be in the bathrooms / en-suite.

 

Extension and the first floor are planned  as timber frame. The intention is to have two good bedrooms upstairs towards the back for the kids and whatever else can be carved out of the remaining space is a bonus.

 

The main difficulty seems to be finding a good position for new stairs which require quite a lot of space and are limited somewhat by the existing internal wall separating the living room. I am trying to use 300mm going with 180mm rise and work on the basis of 2850mm between floors (2450mm ceiling). If 2750 proves to be enough eventually I will lower the rise a bit.  So here are the three options I came up with.

 

In options 1 and 2 you can see where the existing external wall at the back is. I have not worked much on using the resulting ground floor space as it does not really affect planning. We will probably eventually join the bathroom and the toilet and move washing machine and dryer in there.

 

I started with "option 3" (you can see it is much more primitive :-) ) and it is not bad, but all bedrooms upstairs are quirky. Also there is no easy way to add the stairs to the second floor. We can't have these straight away due to community infrastructure levy and TBH don't really need so much space now but I am sure the time will come in hopefully 20+ years when we want to sell and extra space may come in handy. Also for this option we would have to move the living room door by about 900mm towards the front of the house.

 

Options 1/2 let us keep this door and allow for nice kids bedrooms at the expense of the living room and 2 other upstairs rooms.

 

So - any opinions WRT which one to prefer or any other suggestions please?

 

Edit: oops, didn't realise file names will not be shown. Adding...

 

Option 1

 

 

Option 2

 

 

Option 3

 

Edited August 20, 2017 by oldkettle
Clarity

[oldkettle]

Bump

 

North is on the left. There is a slope from back to front - about a meter for the length of the house.

 

Please let me know in case my questions are badly worded.

 

[Crofter]

Looking at option two... if you put some winder steps in, could you shorten the staircase enough to avoid that little boxout in the room above?

[oldkettle]

4 hours ago, Crofter said:

Looking at option two... if you put some winder steps in, could you shorten the staircase enough to avoid that little boxout in the room above?

 

We have winder steps now and hate them as everyone has had a near miss on these already :-( Hence the conscientious decision to go with very comfortable and hopefully future proof stairs. 

[Ferdinand]

Hi agaiin @oldkettle

 

You asked me to look at this thread again. I didn't dive in first time round because I found it tricky getting my head around the diagrams (see further post I will make next) and spent the forum time elsewhere. Here are my comments:

 

Space efficiency and staircase:

 

I think the basic problem with the plans in the post is that space  is not used efficiently - you have lost an entire reception room downstairs to be a staircase lobby, and another entire room upstairs as dead space in a 20sqm landing. Just space lost in those 2 rooms are perhaps 12% of the entire house as you propose to build it in options 1 and 2. Fix that and you get 2 extra not-ungenerous double bedrooms for free.

 

I think the issue is that you have gone for an overly shallow staircase, and made larger compromises in order to satisfy that smaller detail.

 

I love generous staircases, and we had a whole thread about it last year (with lots of personal experiences). Normal domestic staircases are 42 degrees, and something like 34-37 degrees is relaxed. Your rising/going could be something more like 170-180 and 260-270mm, which is relaxed, and could save you about 1.2m on the length if you start the bottom in a circulation space and a straight run. Then theree is no need for complicated wall and floor structures:

 

As @jack put it then:

 

On 15/02/2017 at 15:21, jack said:

With a lot of looking at various international guidelines and commercial regs, we ended up with about 185mm rise and 270mm going.  I find this ratio extremely comfortable and never think about my foot placement.

 

I make your angle 30 degrees, which seem to me to have made it long enough that it does not fit in a normal sized room, so you have ended up with the need to knock holes in walls and put raised areas into floors, and do that strange both-sides-of-the-wall thing in Option 1, which will all make everything else more complicated and more expensive. Not an efficient way to allocate your money. 

 

If you *must* have the 30 degree staircase I think you need to design a big enough room (hall or other) such that the staircase fits without compromising your walls and space efficiency so much. That would be option 3, or possibly something with a double height longitudinal open-plan lounge (would potentially give top light which would help with the lack of side windows) with the staircase as a feature running parallel with the ridge.

 

No of Storeys:

 

Do you actually *need* two and a half stories once you gain the extra rooms downstairs and upstairs? If you do need extra space over that footprint it may be easier to extend back slightly more,as that may reduce your need to survey or upgrade foundations quite so much. Or plan more efficient space use. You might be surprised how little extra you need to extend backwards to gain the necessary space.

 

I am living in a converted bungalow which is not dissimilar to your project in size etc done by the prevous people, and I have nearly 1900sqft (plus a 3m x 3.5m conservatory) from two stories, which gives me five bedrooms plus one reception (or 4+2 etc). One bedroom is huge, and only one is a single - and the rest are generous. And my roofs are partly hipped. Will PM you links.

 

Way Ahead:

 

1 - I think you perhaps actually gave yourself too much freedom with that huge square empty box, and dived straight into details rather than resolving the more general questions first. Most of us aren't including me aren't architects and haven't got the background to instinctively know how to get the coordination of different underlying elements right when starting with a blank piece of paper. We tend to focus on the surface things that we see when visiting a house eg Pinterest and Houzz are full of sexy materials and gimmicks rather than kitchen work triangles, how not to compromise future maintenance of drains by not building over them, and how to live in it in a wheelchair after a bus-running-over experience.

 

I think you need more constraints (architects will tell you that great architecture often happens in the most difficult situations and constrained spaces). Perhaps one could be to try and keep circulation space (halls and lobbies) down to 10-12% of the overall plan rather than 20%+.

 

2 - I would say start a list what you need, and then develop your house shape around it. That list also needs to be contsrained - a summary in one paragraph, and the whole thing in one page. I think that at that stage it may be worth spending £300-500 on an architect for some rough proposals - for which you would need to write a concise brief of your requirements (a good exercise even if just to focus your own thoughts).

 

3 - I think you need convincing on the staircase. I would go out and find some staircases you would be happy with, and measure them. People owning the staircases will not mind and will love the conversation with an eccentric doing their own real research. Do not forget that you can increase the perceived front-to-back dimension of a step by using a bullnose front edge.

 

I would combine this with looking into what works in converted bungalows. Go and view 10-15 with an estate agent as 'potential alternatives to developing our own', and study them carefully.

 

4 - In mine they did a creative arrangement where the staircase runs up over the bath (pic below). The whole staircase and landing and downstairs bathroom fit into a space 4.5m by 2m - 9 sqm, which is about 75-80% smaller than yours and works beautifully, including enough space for a desk at the top of the stairs. Make that space say 5m or so and you can have your 34-36 degree straight staircase with no kite-steps, which lets it go sideways Pic attached. The only thing wrong is that it should be a shower - no point in having the easy-for-old-people option upstairs where they cannot get to it.

 

5 - Make sure whatever you build works when the children have gone. The people who built ours moved before they finished because the kids had settled down and were not visiting so much. They moved into one that was about the size that this one was before they threw £100k (or whatever) at it, and are now knocking that one about. Like yours, this was reduced to three walls and a hole in the ground, and was beautifully done for us to move into with minimal further work. 

 

5 - DO NOT RUSH. Spend the time to be sure you are right now, even if it takes another 6 months.

 

Ferdinand

 

Edited September 15, 2017 by Ferdinand

[oldkettle]

First of all and again, thank you for your reply and suggestions. It is important to me to run my wild ideas past more than just my family and the architect - and you provided just this kind of an input.

 

I did not spell it out in the first post but here is why I went the way of several option.

We started with a very short set of requirements: 2 large bedrooms upstairs for kids, one with on-suite, a family bathroom upstairs, convenient staircase. We had suggestions from our architect. It was immediately obvious the staircase position was the sticking point due to the existing layout. He advised - and I trust him - that rebuilding internal walls would not be fast and would not be cheap, hence we tried to fit the stairs around the walls we had. I promise nothing in my plans came from Pinterest or Houzz :-)

 

I did not try to use all the space in a perfect way, just attempted to make sure it works overall, fulfilling the minimum requirements. I was not of course planning to leave a 20m2 empty landing in options 1/2, rather wanted to see we could put in stairs to the second floor should we choose to have it. This space would be used either for storage or as a walk-in wardrobe until then. We simply don't need another bedroom :-) 2 bedrooms + a guest bedroom + an office as a bonus - more than enough for us.

 

In a same way as I have left some details upstairs incomplete, I have only changed bare minimum on the ground floor, just to see what must be done to get the stairs in (mainly to get an idea of the costs involved). For example, for option three we need to move the living room door. We will probably be merging downstairs bathroom and the toilet and putting a washing machine and a drier in there, but this is a kind of stage 2.

I also fully understand the kitchen size is far from perfect as 5m is too wide for a U-shape. Not sure what to do about it apart from an expensive option with extra drainage run - see below.

 

I happened to consider at least some of the questions you have raised - either because I read this forum or because our architect pointed them out. I have dug out a trial hole and BCO confirmed our foundation is good enough to take the load so no extra costs there. Our existing drains are on the right of the house and AFAIK not under the slab, hence the decision to put all the bathrooms to the right side. The architect mentioned that it would cost quite a bit of money to create another drain run to the left of the house, especially as there is a garage there, probably between 5 and 10K. I found another potentially good configuration with the bathroom on the left side - thanks to your idea with the stairs over the downstairs bathroom. May be there is going to be option 4 after all.

 

Funnily enough I read the original staircase thread and it made me think about the one we'd want. I have measured the stairs in a couple of public places :-) I did the same when I found stair manufacturers presenting at Homebuilding and Renovation show and chose based on that. I ended up using 300mm going with 180mm rise. It is important to have no overhang as the main risk is going down the stairs, especially as we both usually wear slippers: they are not fixed on a foot. My foot is 26cm, my slipper is 28. I may decide to cut the going to 280 or 290 but only if it brings a significant advantage. Oh, and I also used 2850mm as a difference between floor levels: 2450 ceiling + 300mm web-joists + 100mm ceiling + floor structure. There may be some leeway in it.

 

Do we need 2.5 floors... indeed after kids leave - which is hopefully in more than 10 years - we will not need pretty much anything on the first floor: our bedroom stays downstairs, we like it this way. Yet there are 3 reasons why we ended up with this plan having started with hip to gable.

1) Again, the staircase. I could not find a configuration that would let us create these 2 bedrooms with 2 bathrooms based on hip to gable conversion. By the way, we started working on it with an AT a year and a half ago and their suggestions weren't particularly attractive either.

2) The marginal costs. If we were buying one already converted we would be happy with the one you have - it is indeed beautifully done and sufficiently large. But as we have to do it ourselves the picture is different. Our current plan includes significant improvements to the ground floor - and they cost a lot if one hires professionals to do the job! We would also have to strip the existing roof and make good in any case. The quotes for hip to gable only - without ground floor works - were well above 50K as it involved building a completely new roof (not even close to passive standard). Add ground floor improvements, ground floor extension, new staircase, rebuilding the slab - and we are already in a 100K region. We chose to add more and build a proper first floor. Which at least makes it a possibility to get MBC to work on it.

3) The long run : I think a larger house gives a better resale value if we choose to sell eventually.

 

These are our rationales, I may well be wrong on my calculations, again, would appreciate comments here.

 

My main task in the next few weeks is to agree the outer box / openings so that we could apply for planning, otherwise we will likely lose another year. While the application is considered we can finalise the internal layout.

 

Could you possibly link/describe an example of "double height longitudinal open-plan lounge" ? I tried to search for it but could not find an example and have not seen anything like that myself. I just can't figure out how double-height could work with our layout - at least without losing quite a bit of space as well.

[ProDave]

Re going length on stairs. I have never had a staircase with enough going to accommodate the entire length of my slippered foot, and I have never had an issue tripping or slipping.  If you must have a long going, try and match it with a near maximum allowed rise to reduce the number of steps.

 

Go to somewhere like stairbox or pear stairs where you can design a staircase on line, play around with rise and going and see it in 3D

 

We are aiming for a slightly shallower staircase, just because we can but I doubt we will have a going more than 270mm

 

 

[oldkettle]

Hi @ProDave,

 

Thank you for your advice. It may well be many many years living in apartment blocks and working in office buildings (and running up and down the stairs) or just the way I walk or an experience carrying kids or stuff but I just feel comfortable with 300mm run. I will ask my friends, may be somebody around has 270mm and I could have a go.

 

The thing is 30mm per thread saves me 480mm overall. It is something but does it make a significant difference in our case?

Edited September 17, 2017 by oldkettle
Typo

[Ferdinand]

@oldkettle

 

Will reply tomorrow as I am on an iPad at present.

 

Ferdinand

 

 

[oldkettle]

On 27/09/2017 at 11:28, webmaster786 said:

I just want to talk on option two ... if you take a few steps, can you shorten the steps so as to avoid the obstacle in the above room ??

 

Hi @webmaster786,

 

Thank you for your comment. 

We have agreed we could shorten them by 20mm but not more. To be honest we were not concerned about the obstacle as a wardrobe could be easily set on top anyway. But we could not find a good use for downstairs space and didn't like the loss of light and this is why we are trying to work with version 3 now or rather with its variation. I will post proper plans for review soon.