Builder of extensions, renovations, additions to existing homes to increase value. builder of second storey extensions in Sydney

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(02) 4577 4912


Unit 1, No.103 Railway Road (North) MULGRAVE NSW 2756

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Proud Members of the
Master Builders Association of  NSW since 1968
Proud Members of the
Master Builders Association of  NSW since 1968
Beecroft job (BEFORE PIC)
Beecroft (AFTER PHOTO)

First Floor Additions

Carlingford job
Before photo
First floor addition in Carlingford
Mosman job
Before photo
Mosman luxury renovation

Winners of the MBA (Master Builders Association of NSW) Housing Award

Home Extension/Alteration/Renovation (Category $150,000 to $250,000)

The biggest growth area in our projects is now undoubtedly second story additions. With good economical vacant land limited in the Sydney area many people are now opting for a second storey addition in lieu of building a new home.
2nd storey additions are also called first floor additions, attic conversions, Cape Cod extensions or top floor renovations. They are all the same thing but they can be standard construction with frames and trusses or can be constructed using complex pitched roofs with dormer windows. Previously owners risked over capitalising but now in many cases a 2nd storey addition can greatly increase the value of the home and be a good investment as well as adding more space. First floor additions are much less disruptive to home owners than standard additions as work is completed above the existing home rather than in the owners yard.
We do NOT require owners to leave their home while construction takes place. Our workers will enter the house via a window to the 2nd storey, not through the front door. Only after internal linings will the staircase opening be opened up to the ground floor, minimising any disruption to the owners
St Ives Before Photo
St Ives After Photo
St Ives Kitchen / Dining
St Ives Sunroom

There are a few items that require special attention for 2nd storey additions and they include:

  • Transfer of points load
  • Installation method of waterproof tarp
  • Construction program until house is waterproof
  • Air-conditioning
  • Brickwork matching & structural beams
  • Existing house services condition
  • Neighbours privacy
  • Light weight construction materials
  • Removal of existing ground floor walls to open up living areas
  • Power, TV, gas & hot water design 
  • Scaffolding & site safety (especially for owners)

2nd storey additions require good organisation and access to a large carpentry team to ensure the waterproof stage is reached quickly, minimising the chance of leaks. 2nd storey additions are therefore not usually suitable to owner builders or smaller on-site working builder companies.

For second storey additions to work well the builder needs very detailed planning, a dedicated hard working team of carpenters, attention to detail and above all patience. If the weather looks bad the project needs to be delayed at the appropriate time to minimise any leaks. OMara is very experienced at the process of second storey additions.

Completed first floor extension at Stanhope Gardens

McGraths Hill Job Completed

Beverly Hills project (BEFORE PHOTO)

Beverly Hills Project nearing completion November 2012

After signing building contracts we will not commence work on-site for a couple of weeks until a large amount of materials have been delivered to site so that no delays occur waiting for materials. We usually start work on a Monday and the process will involve the following steps;

1. Delivery of materials
2. Relocation of aerial power service (if required)
3. Strip roof tiles / roof and dispose or store on site for reuse
4. Cut back roof timbers
5. Pack up wall frames and install floor joists
6. Install internal drainage for first floor bathrooms
7. Install new air-conditioning ducting as required
8. Install new sheet flooring
9. Install plastic membrane and specialised waterproof tarp
10. Crane up, stand frames & trusses using special fixing methods for 2nd storey additions to minimise leaks during rain
11. Install fascia & gutter
12. Install roof tiles
13. Fit windows & sark walls if necessary

At this stage the house is now waterproof and the chance of any leaks to the ground floor is greatly reduced. Only very minor leaks should now occur. We usually reach this waterproof stage within 15 a few weeks. If the project includes pitched rafters rather than trusses or metal roofing it may take longer to reach this stage. Extremely large additions can also take a bit longer but this time frame usually allows for a 2nd storey addition of around 12m x 8m, a typical size. O'Mara constructions has completed a number of first floor additions using standard construction and alternate building materials. Photographs and references can be supplied upon request.


Concord Streetview

Nth Richmond
Nth Richmond
Nth Richmond
In some instances "Posi-strut" open web floor joists are used which allows for services such as air-conditioning ducting. In other circumstances Hyspan or Hynebeam joists (which are laminated timber joists) are a better option. Sometimes it is better to raise the height of the area between the existing ceiling and the new floor joists. Each project requires careful consideration in the planning stage of which is the most suitable method.
Owners need to select bathroom fittings such as bath tubs, toilet suites and vanity units prior to construction commencement so that the appropriate allowances can be made at the floor joist framing stage. OMara has a special method of construction that is more flexible and allows for future changes but it is still critical that these selections are made at an early stage.
Our experience is that quiet often the existing ceiling space can be very dirty. It can contain old dusty insulation, spray-in type insulation, rat vermin, dead birds, birds nests and many other horrible things. We recommend that all owners considering completing a second storey addition that they employ the builder to clean-up the ceiling space. Upon request we can vacuum out completely the existing ceiling, remove all old duct ridden insulation, install new clean insulation and install downlight protectors (which is one of the biggest causes of house fires) prior to installation of the new sheet flooring, This is the only opportunity the owners will have to clean-up this area as it will then be sealed forever after installation of the new floor.
Please contact our office to find out if a 2nd storey extension is possible at your home and how the process works from design to approval to construction

Second storey extension completed at Castle Hill

First floor extension at Kellyville Ridge

2nd storey extension & renovation at Wahroonga

Wahroonga extension & renovation