1 The cost of materials for a basic 200sf screened in porch on an existing deck in most urban areas should run between $470 and $680, with an installation cost between $296 and $345.  The total cost for a basic 200sf screened in porch will range from $766 to $1,025 or an average cost of $4.48/sf.
A same level house extension in Australia will cost approximately $60,000 to $200,000+. Adding a room or extending your living area on the ground floor are affordable ways of creating more space.Here are some key points to consider that will help you keep your renovation costs in check.enovation costs for a same level extension are roughly between $60,000 and $200,000 depending on your situation, including material, labour and project management (ready to move in). As a rough guideline, earmark around $60,000 for a one-bedroom addition to your home.
As a rule of thumb you can add 50% extra to the build cost of a single storey extension. So, Â£24,000 +50% = Â£36,000. + Add on 10-15% for professional fees (architect, planning application, building regs, structural engineer).+ VAT.o, for your 4 x 5m extension, the build cost would be roughly Â£24,000. + Add on 10-15% for professional fees (architect, planning application, building regs, structural engineer). + VAT. Single storey extension = Â£32,000.