There are many factors that are likely to influence or add to construction cost. Some of these factors are:
- Location & Site Access
- Unique design details & Finishes
- Availability of labour
- Market conditions
- Inflation
- Latent site condition
Below are some of the strategies to reduce the number of variations, and to have a better cost control during construction;
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Comprehensive working drawings
- During the tender stage, all potential builders should be provided with a good set of clear and thoroughly drawn working drawings. This is one of the most important documents for them to understand the scope of work. You should not leave anything out or have anything drawn in a way that can lead to different interpretation.
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Specification and fitting and finishes schedule
- Be specific with what you want and the level of result you expect. Have a good discussion with your Architect and ensure that everything that you wish to have are included and selected in the specification and schedule. Even if you aren’t entirely sure about it yet during the tender stage, include them as prime cost items or provisional sums.
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Do not have too many Prime cost & Provisional sum
- There is a risk of having too many price cost items and provisional sum. Running this risk can lead to a higher chance of variations. Over reliance on these estimates can result in inaccurate conclusions concerning the total contract price. This then remains subject to adjustment as each price cost or provisional sum is finalised. Besides that, they might be a long lead times to ordering of many specific building materials. It is important to clarify with the builder if the provisional sum includes all relevant materials and works associated with their installation or simply the cost of installation alone. Confirm that the contractor has allowed for installation of a price cost item yet to be selected.
It is vital to have an adequate amount of contingency sum. Each construction project generates its own difficulties which time will expose, and provision of contingency sum is a widely recognised mechanism to allow these to be overcome. For new works, the contingency sum should be in the order of 3% to 5% of the estimated cost of the work. For addition & alteration work, it could be up to 10% of the cost.
Howard Siow
Graduate
M.Arch (MELB) Hons, RAIA
BY Projects Architecture
09/07/2017
I highly recommmend the team at BY Architecture.
Barbara, Howard and the team designed a wonderful extension to my late 1960s Melbourne home, ran the tender process to find me a builder, and superintended the build contract.
The design process that Barbara took me through was comprehensive, well-considered and highly collaborative, and the resulting extension and renovation was incredibly well-tailored to my specific needs and desires.
The tender process was similarly well-run, and we ended up choosing a builder that Barbara had worked with many times before and recommended. The recommendation was a great one and the entire build ran very smoothly, with the many quirks arising in a typical renovation being dealt with intelligently and with no fuss.
During the entire time I worked with them, Barbara and her team went over-and-above to keep me happy. As a result of their attention to detail and their focus on customer service, they ensured that what can often be a stressful time was actually a pleasure. I cannot thank them enough and would work with them again in a heartbeat.
Barbara, Howard and the team designed a wonderful extension to my late 1960s Melbourne home, ran the tender process to find me a builder, and superintended the build contract.
The design process that Barbara took me through was comprehensive, well-considered and highly collaborative, and the resulting extension and renovation was incredibly well-tailored to my specific needs and desires.
The tender process was similarly well-run, and we ended up choosing a builder that Barbara had worked with many times before and recommended. The recommendation was a great one and the entire build ran very smoothly, with the many quirks arising in a typical renovation being dealt with intelligently and with no fuss.
During the entire time I worked with them, Barbara and her team went over-and-above to keep me happy. As a result of their attention to detail and their focus on customer service, they ensured that what can often be a stressful time was actually a pleasure. I cannot thank them enough and would work with them again in a heartbeat.
Barbara is very friendly and easy to work with. Thank you for the great advices.
Response from the owner 23:14 17 Jun 24
thank you Arik. Happy to be helpful 
Barbara and the BY Projects team were fantastic to work with for our knockdown-rebuild. We had no idea what we were doing or getting ourselves in for, and through every stage of the process Barbara explained everything and was supportive and transparent.
She drew plans for a beautiful house for us which fulfilled everything we wanted while adding such flair and style that we never could have imagined ourselves.
I was so glad to have her and her team on my side throughout the build process, as we would have struggled to advocate for ourselves (or even notice) mistakes or defects by the builder.
Overall, we just couldn’t be happier with the final result.
She drew plans for a beautiful house for us which fulfilled everything we wanted while adding such flair and style that we never could have imagined ourselves.
I was so glad to have her and her team on my side throughout the build process, as we would have struggled to advocate for ourselves (or even notice) mistakes or defects by the builder.
Overall, we just couldn’t be happier with the final result.
Response from the owner 06:53 31 May 24
Thank you for your enthusiasm Emily. And thank you for trusting us with your dream Home. It's been a pleasure working with you and your family, and we trust you will enjoy your home for the years to come. 
We recently had the pleasure of carrying out a renovation for Barbara and BY Projects Architecture.
The project ran very smoothly from receiving the plans, to handover day.
Barbara pays very close attention to detail and takes great pride in her work.
We look forward to working with BY again on future projects.
The project ran very smoothly from receiving the plans, to handover day.
Barbara pays very close attention to detail and takes great pride in her work.
We look forward to working with BY again on future projects.
Response from the owner 22:11 30 Mar 21
Thank you Koray. It was a pleasure working with AMCON Homes, we look forward to working with you again in the future. 
Barbara provided excellent professional advice regarding Town planning and approval process by the Council. She went out of her way to find the right information and help me. Will surely use their services again when necessary.
I would highly recommend them.
I would highly recommend them.
Response from the owner 01:37 16 Feb 21
Thank you Jarardhan. We do hope you find a more suitable site soon to build your dream homeBarbara 
We were in a very difficult position after a VCAT rejection. Barbara came into our project and reimagined what was possible with our property. Going from a house with three shops with significantly reduced value to a development with two town houses, a cafe and all able to be subdivided into three separate properties. Barbara was positive, enthusiastic, charming at planning meeting and all in all kept us positive and hopeful. Barbara went through the whole process with us and I would say went above and beyond what would generally be expected. She worked well with our development team, working out strategies for planning challenges. We are very thankful for her time and energy.
We engaged Barbara and her team many times over many years for our Building Development Projects, including Multi Residential, Child Care and Mixed Use. Most recently for a couple of houses in Port Melbourne with complex Heritage Overlay requirements.
Barbara worked with us closely to ensure all design requirements were achieved to exceed market expectations. All permit requirements were managed in a professional and timely manner, and all processes were met on time and on budget.
The finished buildings were outstanding and the realized sales well above market expectations.
We highly recommend BY Projects Architecture for their Design sense and construction experience.
Barbara worked with us closely to ensure all design requirements were achieved to exceed market expectations. All permit requirements were managed in a professional and timely manner, and all processes were met on time and on budget.
The finished buildings were outstanding and the realized sales well above market expectations.
We highly recommend BY Projects Architecture for their Design sense and construction experience.
I have worked with Barbara and the team at BY Projects on a number of projects now. Its hard to think how you could get better value for money. They are great architects - that goes without saying. But its the extra mile they go to on your behalf in order to secure the very best for you that makes all the difference. I wouldn't hesitate to recommend them for your next project.
Response from the owner 06:02 24 May 19
Thank you Virginia for your kind words. It is always a pleasure working with you. 
