Renovating and extending a Pettit and Sevitt home.
Alistair McLean
Category: Renovations

Alistair: Posted on Thursday, 17 January 2013 2:12 AM


It has been a while since Secret Design Studio has posted anything on this blog, so my apologies.  In my last posting I wrote about moving to the new office which is still a work in progress, and the new website.  I propose to run the new website in parallel with this one for the next few months so it gets some traction with the Google search engines.

I have also been putting a bit of effort into Secret Design Studio’s Facebook page, ( which has a nice immediacy to it, better feedback, and so it is easier for me to tell what is working and what isn’t.

If you are one of the last three people in the world who are not on Facebook yet this could be a great reason to join so that you can follow more interesting Mid-Century modern stuff from Secret Design Studio, usually with an Aussie slant.  If you do decide to join Facebook to follow Secret Design Studio then I promise I won’t stalk you, and you have to promise you won’t post photos when you are too drunk.


I recently had a query from one of Secret Design Studio’s Facebook fans about her Pettit and Sevitt home in Sydney’s north and where to start with a house that needs everything.  I started composing a reply, but it got longer and longer, and as a lot of it may be applicable to renovating and extending many mid-century modern homes (including the Pettit and Sevitt variety) I thought that the information would be more valuable in this blog.


Ms C asked on Facebook:
“Hi SDS and SDS-aficionados, we have a Pettit + Sevitt Split-level Mk 1 in Sydney’s north, and we are looking to renovate. (I know this may horrify purists but it’s not in good condition and needs new… well, almost everything.) We also want to extend it a bit, but still keep the character and basic layout. Can you or your followers recommend a design & building firm in the area that will be sensitive to the original style and design? We’re on a sloping bush block so we have the added challenge of that, and meeting the new bushfire compliance requirements. Thanks in advance – any tips would be appreciated.”


Secret Design Studio reply:
“Unfortunately most people (including most builders) don’t appreciate Pettit and Sevitt homes so there isn’t a large enough market for a design and build company to specialise in this area.  Most of the design/build renovation and extension companies in Melbourne employ in-house drafts people.  Often they don’t have an architectural appreciation of mid-century housing. They will try and change the character to the current display home fashion and try to cram in a home theatre, acres of polished porcelain tiles and greige paint throughout.  I am sure that the situation is similar in Sydney.
It is really difficult to make many recommendations without knowing much about the condition of your home, your site, and your budget, but I will try and give you a couple of general ideas.


In my experience with Pettit +Sevitt houses of this age (I know of at least three through my work) you will probably be looking at a new kitchen, new bathroom(s) and possibly a laundry.  The bedrooms will be fairly compact, so you may be looking to improve these, and you probably have a single open plan kitchen/dining and living area. There will probably be a shortage of power points for today’s living, and the wiring will be nearing the end of its safe life. You have already identified the need to meet the bushfire requirements, but you will also need to look at the BASIX requirements for energy efficiency and sustainability, which can also make a dent in your renovation budget.

Externally there may be wood rot to the window frames and some of the exposed roof timber and fascia, but the brickwork will probably be in reasonably good condition, and may just need a clean and a repaint. The front door may lack a sense of entry by today’s standards, which can be overcome by landscaping and a bit of careful design.



For potential clients I recommend they engage a professional design service (such as Secret Design Studio) who can complete a full assessment of your home to establish exactly what work needs to be completed and to help you work out the priorities in a logical manner that works with your budget. If you are one of those rare clients who doesn’t have a budget limit then ring me today and I’ll see you tomorrow!

For the last Secret Design Studio Pettit and Sevitt house that I worked on, which is in Beacon Hill, (Northern Beaches of Sydney) I completed a pre-purchase inspection. During the inspection the client said that she hated the daggy but functional 1980’s kitchen, which had been added in much later as part of an extension, and it would be the first thing to go.


After she purchased the house I was engaged to complete some design concepts that showed how the house could be better utilised for her lifestyle.  One of these concepts was to build a new kitchen on the opposite end of the house to the existing kitchen.  This new kitchen would have its own external door which would lead out to an adjacent (and delightful) outdoor dining area with great views.  The existing arrangement was to carry food and drinks through the length of the whole house to the front door and out to the outdoor dining area!

However there were a lot of other expenses that needed to be met.  As a result of my work, she has decided to live with the functional, but ugly 1980’s kitchen in the short term and not spend any money on it to make it look better. In the future she will build her dream kitchen, with a decent budget, then demolish the 1980’s kitchen, which will be converted to a new master bedroom suite with a great view.


I don’t know how long you have lived in your home but I always suggest to clients that it is a good idea to live in a home for at least twelve months to get a good understanding of its pros and cons.  For instance is late summer afternoon sun a problem?  Is there a place to sit and read a book in the sun in winter? Does the bathroom have adequate ventilation? Do the kids need supervision when working on their laptops?

When renovating any period home you may need help to work out a balance between authenticity, practicality, legislative requirements and cost.

As a simple example you may need to replace a rotted out timber window frame.  You could probably replace it with another timber window frame with similar sized timber members which is fairly easy.  You probably would not go to the trouble of machining the timber to the exact dimensions of the original, unless it was in a bank of matching windows and the different sized window frame may be noticeable.


While replacing the window you may consider double glazing options to improve the energy efficiency of the house, especially if it is a room with a view, and you would like to avoid having window coverings. While there are cheaper options to a double glazed, timber framed window, such as powder coated aluminium and PVC, these would be dismissed if you are trying to keep the original style of the home.  The design of the window may also be influenced by the BAL (Bushfire Attack Level) so that the original design may not meet the current BAL requirements.

Getting all of the correct details and information is crucial to communicate with your builder, especially if you are trying to maintain the style and feel of a Pettit and Sevitt home, or any mid-century home, with 21 century building practice.

For example Secret Design Studio had a Pettit and Sevitt client who had previously replaced a primary window and the architrave surround in the living room without any design advice or input.  They had assumed the builder involved would know what he was doing for such a straightforward job.   Throughout the whole house the skirting boards and all the window architraves were the original dark stained timber which was like a Pettit and Sevitt signature.

The builder completed the work with the new architrave in a contemporary pre-undercoated MDF (Medium Density Fibreboard) which has no timber grain and requires painting.  When he was queried he explained that he always used MDF as it is easier to use, it doesn’t split, it is easier to paint, and is purchased with an undercoat, which is all true.  There was nothing wrong with his workmanship, the fine print did say “MDF architraves” in the quote, and a quality timber for staining would have been a lot more expensive. He suggested that it would be better for the owner to paint the dark stained timber skirting boards and architraves (which he didn’t like) to match the new architrave rather than replacing his pre-painted MDF architraves with timber!

I think it is true to say that most builders understand building, but not all builders understand design, and even fewer understand why anybody would want to preserve the style of a house from the 20th century!


The best way to find the builder for your home is generally via word-of-mouth with friends and colleagues.  Secret Design Studio has worked with one great builder who is based in the northern suburbs of Sydney who I would recommend, however great builders are never the cheapest, nor are they the most available.  Beware of the builder who is prepared to give you a price when you tell him what you want when you haven’t even got plans. Your quality timber expectations will always be a lot more expensive than his MDF pricing!

The beautiful Pettit and Sevitt home and addition featured in this blog is not the work of Secret Design Studio. It has been sympathetically extended by the current owner who is a friend, and who is an architect that I studied with at Sydney University. I hope that the photos inspire others to realize that good design that is carefully executed can actually improve the value of a Pettit and Sevitt home more than a contemporary (and unsympathetic) renovation, which will appear dated before too long.  If you look carefully you can see where some contemporary materials have been sympathetically used, yet it has been done so carefully that they do not detract from the character of the original home.