I have had builders tell me both sides of this - yes, it will cost more. No, it need not cost any more [to build up]. Architects also seem divided. So I am eager to see what others say here...

Honestly, I doubt any architects doing this type of work in the real world will disagree that it's 100% one way when dealing with going up within an existing structure. It's a typical dilemma/issue & something we deal with regularly because people (generally) have little understanding the about practical/cumulative costs involved with design options one way or the other and it's hence our responsibility (when engaged) to demonstrate and resolve a logical solution to budget. How best/most cost effectively to achieve the requirements in context? Do you extend out or extend up. I've commented on this/similar topic previously but as a rule of thumb as Retro said any day of the week going up as opposed to out will involve higher cost, way higher. Physically Higher Building = Practically Higher Cost. Why? For many reasons but the primary ones are because going up involves (a) greater scope due to usually involving more rejig to existing spaces to accommodate the upper level as well as making the most of the opportunity that then logically in realestate terms the conversations ventures into "well if you're going up then we might as well include the extra living or extra bathroom or whatever (b) higher construction cost due to being a more complicated build process and more OH&S related stuff (c) more complicated structurally which then can involve knock on effects to remedial on the lower level in order just to get the structure in.

BUT, this doesn't necessarily mean that going up is not the best option in a particular context. It depends on what is trying to be achieved and needs to balance out many factors including existing conditions, proposed overall building program (including internal and external spaces/requirements), existing and post-project property value and available capacity to finance a particular budget. Sometimes going up makes sense, particular when the whole lower level requires a re-jig/makeover anyway and hence it deemed logical to capitalise on the opportunity. This is about investment analysis and making smart decisions for a long-term end result.

It's important to understand too that the smaller the scale (reno/extension) the higher the cost per m2. To lower this cost/m2 to a point that it makes sense for the investment sometime it involves actually upscaling the project to achieve the best bang for buck. We also can't utilise/transfer volume build m2 rates into the renovation/extension world: they are literally worlds apart.

It's complicated, and so how to make sense of this? How to achieve clarity in regards to the best way forward in these situations. Well, we provide what we call a Feasibility Stage of service in which we consider a particular set of requirements in certain context, and develop broad form scenarios in different formats that are professionally designed and costed. Eg Client comes to us needing an additional bedroom a 2nd living, Kitchen update and a 2nd Bathroom. How to achieve it? You could do this in various formats: you could go up or out, but how exactly and how far do you go? How much work will be required to the existing? Ultimately it will come down to money/cost and if this is not understood and managed robustly at the time of design (which as an aside "design" needs to be differentiated from "drafting") then you end up exactly where Nadine is here - back to where you started blown away by the quotes questioning the whole project.....

As design professionals it is our job/responsibility to answer these questions and resolve viable options with properly developed and costed scenarios so people know exactly what "package/option" is (a) viable in context and (b) realistically going to cost, so the project direction can be understood in terms of investment value as result+cost package, and not just one or the other. We can demonstrate how in context the different options sit and at what price points before you even think about a builder. If anyone has a similar dilemma and feel stuck with how best to approach or work through the options to balance their budget, you may be interested in our service in which this stuff is professionally dealt with and managed properly.

Hope this helps, and hope this gives people some hope that there are solid answers for this stuff, but it requires professional design service & assistance. Cheers :) PD

Sometimes going up is a better (only) option. Sometimes extending out is the best. Cost wise is as touched on above. Scaffold adds up quickly as does manual handling be it up a level or just poor access on a single level extension. Site coverage for council is another where going up is your only choice or even existing dwelling layout may just be suitable for a single level.

Lot of factors to consider but a good designer should know all this.

I've just finished plans for two separate clients that don't know each other, houses in same street just 4 allotments apart..... One is suitable for a ground level add the other is to go up as the only option....

Wow thank you all for such detailed, straight up answers, I really appreciate it and yes never actually considered things like the extra floor space for a staircase and the extra cost for the scaffolding...renoing your own home is both wonderful and bloody hard!

Also realized I probably should have given some more details-when we were planning on building out we worked out the kitchen we'd like (open plan and finishing up onto the deck via a servery window) and that required 5ms and then 4ms for a deck (current one is 3ms and feels very small to fit an outdoor table) and a new bathroom-the roof is tiled and also has asbestos so it needs to come off and be raised up- the quotes I've had back have been around the 200-280k mark which is way out of our budget. So building up would be more than this? Let's say to put 3 bedrooms, a WIR, ensuite and bathroom upstairs and shift laundry downstairs?

Thanks so much for your help/thoughts, it's been really appreciated :)

Knowing how complex first floor builds are, plus you are adding two new bathrooms (which are expensive rooms to add), plus a lot more extra square metres to accommodate the three bedrooms, WIR and stairwell, I would be looking at doubling your budget range for starters to add another floor. The sky really is the limit, as you don't know how much remedial work you will need to do on the ground floor to support upstairs, and to conceal all that new plumbing.

With your budget I would consider staging your single level project, perhaps doing the covered deck as stage 2, with a simpler roof. Smaller renovations like yours are the most time consuming, and least profitable for builders, hence the price tag.

Did you use a design professional to make the most of every square metre work for you, or just say our new kitchen will need to be about 5 metres long, so we will make our house 5 metres longer? Does your new deck really need to be the full width of the house to accommodate a 7 metre long table or something? Every square metre of new construction costs money, so have you considered reducing the size with a smarter design?

Lilyfield House · More Info

Best of luck,

Dr Retro

of Dr Retro House Calls.

100% Nadine, building up on that project scope, no matter what it is or where it I guarantee will be WAY more than $280K. As I said, you need to be working with a design professional who inherently understands construction budgets and how to properly manage them within the design/proposal and also manage the client's expectations in the process of working through it all. I see and hear of this situation time and time and time again, & pretty much the common thread is that budget is not properly understood or managed competently. When assisting people in these exact situations and hence in a position of responsibility providing design consultation & advice, the information we prepare and provide is not always what people would like to hear, but rather it's what they need to hear, ultimately for their best interests and so that they can begin to think and make decisions productively and realistically work towards actually achieving something with their available budget. More often than not this involves helping people to understand and acknowledge the limits and then rationalise exactly where they are willing to compromise and prioritise when push comes to shove. It's also equally about recognising opportunities so a budget constraint is not all doom & gloom, but it requires creative negotiation, which is generally the difference between a design pro and anyone else and the value of what we can provide, in that we'll recognise the limits, but work out how best to maximise the value of a nominated investment limit in a particular context. Champagne dreams on beer budgets is a widespread problem, and it's compounded by various issues such as the media/TV and volume build marketing providing public with skewed expectations on what construction truly costs, as well as some builders providing low quotes with arguably unrealistic contract allowances embedded that are primed to blow out and furthermore, probably most significantly, the absence of proper design investment, and just having "plans done up" by operators who disregard or incompetently manage the budget constraint factor. Super frustrating for all involved and looking on in, but ultimately (& unfortunately) most significantly for the homeowners who are just trying to achieve results for their homes and their families.......the best advice I can give is front end your project with experienced professional design advice............best of luck with it :) Cheers PD

Nadine - I have been through all of these dilemmas in the past year - the up vs out argument! The professionals in this thread offer great advice and lots of it rings true. For us personally, we were told that the going up option would be more expensive but it wasn't a crazy amount more - like say $15-20K. HOWEVER we live on a sloping block and were told by our architect and different builders that the potential for expensive latent conditions is always there with our block. So we opted for going up as I just didn't want the worry what would happen when they broke ground.

It's costing $280K for a first floor addition (and some extra ground floor) of 80sqm. This includes a new dining room, two new bedrooms, WIR, a new master bathroom and refit of an existing bathroom and laundry. One thing I would mention is that a lot of people don't realise how expensive it is to knock down and relocate walls within an existing space. It can work out to be a lot more than building from scratch.

Good luck!

Yes Mumof2g - good to hear your story/experience, and this demonstrates how it will always depend upon the specific context as to which option is best in a particular case. You're 100% correct in that people not understanding/underestimating costs on reconfiguring existing - it literally gets to a point/threshold with these jobs over which it's debatable even keeping any of the existing. The constantly shifting Labour/material cost/ratio (where by now labour build components far outweigh the material elements, in this country anyway) now render the more "resourceful/preserving" approach that was pursued with logic in bygone eras virtually now irrelevant and certainly not economically beneficial. Which is why when we are dealing with renovation/extension projects, they need to understood and managed completely differently to New Custom Builds and Volume Builds. These are all inherently and fundamentally different categories of beast! Cheers PD :)

Is there an opportunity to do an extension where you don't mess with the roofline? Changing up the roof is always the most expensive thing from what I've been told by experts. https://www.houzz.com.au/pro/undercoverarchitect/undercover-architect The Undercover Architect often turns up on these threads encouraging a small link building and then a pavilion extension.

Here are two projects to give you an idea of what I mean:

Check out this story from Houzz - https://ml.houzz.com/HCdS1RkUgN

Aaaand this fancy one.

https://christopherpolly.com/projects/binary-house

Totally agree with Alexandra, if you have the space a linked Pavillion extension is the best option

Yes a "clean" extension that minimises work to existing is always the lowest cost customised option. It doesn't necessarily equate to cheap, however it will maximise the investment in regards to property value. Of course you require the land/space available. It's amazing what you can achieve in a small footprint. We recently completed a stage of work on our own home in which we snuck in a two storey extension to the side, only 30m2 odd footprint to significantly improve/increase the growing family home function to include 2 walk in robe spaces (that double as a link), a rumpus room, stairs to a mezzanine area, a 2nd TV/reading/library area, a kid's study space and an abundance of general storage. Albeit I played around with it architecturally, and that translates to cost relative to finishes/articulation - a snapshot of it below:

the result 100% compliments the existing residence literally without modifying any of the existing (we had previously completed earlier stage full renovations) except narrowing 1 single window sash. Of course, it all comes back to design and understanding the whole residence/property and balancing it all out with an appropriate solution to budget within context

Going up involves stairs which are a cost in themselves plus they will add approx. 3-4 sqm x 2 to fit them in on both levels so stair space alone will increase your build cost. Hidden costs such as scaffold hire will add to the build cost that you don't get anything back. It's simply an added cost. Then there is the need to upgrade your lower floor bracing to transfer the added wind load created by the second floor addition. Then you add on site safety compliance costs. It may take longer to gain building approval with council needing to consider shadows and privacy issues etc then it will take longer to build which will cost more in interest payments while you wait. All practical unavoidable costs on top of your single level addition cost. Unless you have no choice due to site restrictions or will unlock added value in your home by capturing a view then keep your feet on the ground and enjoy the flowing open plan addition that will breathe new life into your home.

Nadine, friends of mine are going up and adding approx. 85sqm going up (2 bedrooms, a bedroom size study, a lounge area and a bathroom with shower). They are also re-doing and enlarging the master bathroom and adding a master walkin wardrobe downstairs (this involves removing some walls). Total cost (excluding toilets, vanities and sinks) is $300,000 including plans.

Possibly the removal of the asbestos is adding substantially to your costs?

You definitely need to get some more quotes.

Hi Nadine,

I agree with other people here that a pavillion extension is a great way to go. I live in a heritage house and we are undergoing planning to have this done. Quotes for putting just 2 small bedrooms upstairs were above $100k. We are instead doing a 2 story extension on the side of the house, which can be fully built and then when ready, a short 1 metre corridor constructed to join to the existing house. No need to move out or have any impact while its being built.

We are also having ours done as a pre-fab steel shed done to residential specs. The slab, construction, insulation and lining will cost us about $45k, and its 6.5m x 9m with two mezzanines to make upper floor bedrooms, with a grand double height void in the middle. This price is just the shell essentially, but far cheaper and faster than traditional construction. You can then go to town on high spec interiors (and have the money to do it.)

This is a favourite of mine, being creative as Architects are known for and giving his son a very affordable extension cheers

https://www.domain.com.au/news/shed-provides-affordable-extension-20110128-1a7yk/

there are various ways to skin a cat so to speak. It's about finding the right balance for the particular context and depends on priorities. Usually, it will cost what it will cost and there are pro's& cons always to weigh up for various aspects. As a rule of thumb it's going to be 50% to lock-up and then the same/similar again on top to fit-out give or take depending upon what's included and to what quality. The question as always is what is the best value and bang for buck and this is where spending time and investment front end in considering/researching/weighing up the options and alternatives can reap the rewards.

Hi ALexandra,

will be doing vertical cladding in dark grey, with wooden double glazed windows. These will be stained and varnished dark red wood colour, which looks amazing against grey cladding. Ironically I live in Canberra, but found a window place in Melbourne where it’s almost half the price to get all windows made there and shipped up than having locally made double glazed wood windows.

prett much every shed can be built to residential specs.... it’s mostly about thicker slabs and footings, and insulation. You are also a bit more constrained in where you can put windows. The great thing is though, that all internal walls are not load bearing, so they can be moved easily and you can get long span rooms.

Hi Siriuski,

see comment above. Depending on where you live, contact the nearest shed supplier. I am using shedsnhomes. Most of these shed companies have local franchise owners. You are much better off finding a company that does the supply and build, at least to lock up stage. You can also get them to do the fit out, or once it’s at lock up with windows installed, do the fit out at your leisure. Google shed house and just scroll through the images for ideas. Check out these two links https://www.trendir.com/shed-house-built-from-sheds/ and https://www.domain.com.au/news/shed-provides-affordable-extension-20110128-1a7yk/

get yourself a cup of tea and enjoy!

Hi all, I can't seem to reply individually to your comments so here's a general one :)

Thanks all for the suggestions and experience-I'm really intrigued by these suggestions of pavilion extensions, those links you attached Kate are super striking! Unfortunately for us we are on a fairly small block of land and one side of the house is a narrow driveway-we looked into building a garage/study on the ground but as we have to be 900mm from the neighbouring fence it was going to be very skinny and just not worth it.

I appreciate the thoughts shared on keeping our feet on the ground but as we've two young kids and two dogs (and would love to have chickens again) I'm less and less inclined to give up more of the garden which is what we'd have to do if we extend out. Our verandah roof was done back in the 60's and slopes down and leaks in the rain so hence it needs to be lifted up if we were to build out.

Kate, I LOVE your idea of the shed! We actually converted a massive steel shed into a gorgeous shed home when we lived in QLD on a massive rural block of land, loved how easy it was to 'knock' down a wall! :)

Sadly we have learned the hard way that trying to save money by hiring a draftsperson that didn't ask us what our budget was has cost us time and money, but I guess in a way I'm grateful as this extra time has given me time to consider building up now instead of out. I'm getting a sense that it will be a lot more expensive to do so so might have to wait another 2-3 years to get re-finance happening. In the meantime we are making some changes to the current set up, slowly adding value and making it more enjoyable to live in :)

Hi Kate Many thanks for the info, I have just seen your message, very much looking forward to seeing how you get on cheers

Hi Nadine,

Going up is certainly more expensive but something for you to weigh up.

You might find this extension cost calculator useful to compare the options.

Regards Richard@themakeovergroup (Melbourne)

Go away

Cropper Bros - can you please stop putting your advertising for various things on old posts! It is inappropriate to use this forum for free advertising - especially when it is completely irrelevant.

Tag them

Yes siriuskey, I did tag them and it looks like houzz has removed the posts I tagged...

Hi robandlyn I don't even like to validate these posts by responding sorry I meant Flag not Tag