Updated July 2024 by Andrew Mackintosh
What to Look For When Buying a Home with an Enclosed Verandah
Are you looking to buy a home with an enclosed verandah, but are experiencing issues with the roof pitch? This is a common concern amongst home buyers, but being well informed is the best way to protect against future problems.
Everyone knows just how important it is to have a roof over our heads – proper shelter is a basic human right. It is especially important when searching for a new home that you take note of the health of the roof on each house you’re inspecting. In the case of pitched roofs on homes with enclosed verandahs, there are a number of issues that can arise that can be both frustrating and expensive. Read on to find out what you should look for to ensure the roof of the house you choose will keep you and your family safe for years to come!
If you’re purchasing a property where the seller has added an extension or enclosed a verandah, I advise you to speak to your conveyancing solicitor about Council Permits. The seller’s dream to create a room at legal ceiling height may come at the cost of the gradient on which the roof slants, aka, Roof Pitch. Some sellers will simply go ahead and do a renovation or extension without getting Council planning permission. This means that as the buyer, you’ll be responsible for any problems that arise from their “DIY renovations”. If the renovations aren’t registered with Council, you’ll need to speak with your lawyer about where that leaves you legally. Roof pitch is a tricky one because, as a pre-purchase building inspector, it’s not something that I can accurately measure. What I can do is to take a close look at any “suspicious” renovations and if it looks like the roof pitch is at risk of being too low a ratio, I will advise the buyer to get a builder in to check. Roof pitch is important, for safety and for drainage.
What is a pitched roof?
In building construction, roof pitch is the numerical measure for the steepness of a roof. Roofs can be flat or varying degrees of steep. The pitch determines which material can and cannot be used for sheeting, with corrugated iron having a minimum pitch of 5 degrees specified by the manufacturer. Tiles have a minimum pitch of 15 degrees. A 45 degree pitch is actually considered very steep.
When would issues arise?
When a seller has chosen to enclose a verandah to create an extra living space, or add an extension that needs to be “legal height” they’re retrofitting a new room against the existing roof. The roof is already pitched from it’s highest point to the lowest point to allow for maximum drainage. So the roof’s lowest point, is the extension’s highest point. There my not be much “head room” left if the roof pitches correctly, so the “cheeky” way to get around legal ceiling heights, is to create too gentle a slope in the roof. A patio or verandah is not intended as an internal living space, so the pitch of the roof is not as important. But when you enclose that space, adding ceiling paneling, the issues begin.
What are the common pitched roof issues?
Obvious or unseen problems with the roof of the home can become a hugely significant expense. You definitely need to check out the roof of the place you’re thinking about buying carefully to save yourself that heartache in the future.
Roof problems can be worse in cyclone-prone areas. If the frames don’t have adequate bracing and support and aren’t properly secured, they can collapse or even peel away in the wind. Check to see if there is much of an overhang, as the wind can create an uplift underneath and cause the roof to detach from the walls.
We’ve got a few other notable issues here that often arise with roofs. Check them out and take note – your Action Property Inspections expert can help you decide upon the property that’s right for you!
Drainage problems
Roof pitch is also a vital consideration when it comes to choosing suitable guttering and roof plumbing for your property. Roof pitch is an issue that affects how susceptible your roof is to problems such as blocked gutters and downpipes, too. Drainage problems can cause considerable structural issues and roof damage.
You have to calculate roof pitch correctly in order to avoid these drainage problems. As a rule of thumb, the flatter your roof, the more susceptible it is to drainage problems. For that reason, you should only use certain materials on certain roofs. Use the wrong materials and you’ll get a build-up of debris and moisture which can backflow up the roofing material, causing water ponding, stagnation and eventually, ingress. Only then will you realise you’ve got a roof leak. Often, by then, the leak has done considerable damage. Left for long enough, your leaky roof can cause mould and mildew, timber rot and attract termites who love a warm, moist environment.
Roof pitch problems that leave you with a leaking roof call for leak repairs, even replacement of the entire roof, which is a costly exercise. That’s a bitter pill to swallow because you can avoid them if you calculate the roof pitch correctly in the first place and a select suitable roofing materials accordingly.
Roof leaks
Roof leaks can occur for a multitude of reasons. Leaking roofs are major sources of building damage so it’s an absolute must to ensure your roof is watertight. Blocked gutters or downpipes or even rusted roof sheets can all cause leaks, which can lead to sagging or warped roofs, decay damage, mould growth and major damage to the house itself. Broken roof tiles or dislodging tiles will also cause leaks.
The roof needs to be kept free of debris, with the amount of cleaning depending on the pitch of the roof and the number of trees around the house. Check to ensure the roof sheeting is properly nailed down and that any skylights or vents are properly sealed. Check for damaged roof pointing or cracked roof tiles.
Guttering and downpipes
The most common problems with guttering are poor drainage systems and leaf build up. These cause water to build up in the gutter, leading to corrosion well before the gutter should be prone to it.
Gutters collect and divert rainwater to protect the house and its foundation. This should also reduce erosion, prevent leaks in low lying spaces and protect painted surfaces by reducing their exposure to water. If you see any water damage in these areas, the gutters aren’t functioning properly. Gutters need to be installed with a fall so that the water runs through to the downpipe and drain. If this isn’t adequate, the water collects and corrodes the gutter, which leads to a host of annoying and expensive problems. You should ask your Action Property Inspections inspector to check the angle of the pitched roof and ensure that the current downpipes and gutters are correctly installed.
Roof pitch places limitations on design and materials in a roof
Your roof pitch or slope is one of the factors that might limit your choice of roofing materials. Manufacturers’ specifications and Australian standards dictate what roofing materials and construction methods are suitable for roofs with a particular pitch.
Roof pitch can also affect the design and appearance of a property. For example, it dictates whether you can have eaves on a property. It also has a direct impact on street appeal, as properties with flatter roofs will be regarded as less attractive than their steeper-sloped counterparts by some potential buyers. A more sharply pitched roof also lends itself to greater potential to more effectively utilise the roof void for storage, extra accommodation or implement character features such as soaring ceilings.
Roof pitch is also a relevant consideration when it comes to building design at the very earliest of stages. Generally, if your building is a very large one, the roof pitch will be lower because the dimensions of the building would otherwise necessitate an impossibly tall and prohibitively expensive roof. Generally speaking, the bigger the roof, the flatter the pitch for that reason.
Also, the steeper the slope or pitch of a roof, the more materials required to construct it. In this way, the overall cost of a build or renovation is directly affected by roof pitch.
Roof pitch safety and access considerations
Roof accessibility is a factor that is also determined by roof pitch. It has a direct bearing on a number of safety considerations that come into play when you’re considering carrying out work at height. Roofs that are steeply pitched call for more rigorous safety regulations, for starters.
If you’re getting a tradesperson to carry out the work, occupational health and safety regulations and Australian standards might mean they have to use specialised equipment such as harnesses and roof scaffolding to work on your roof. It may be more difficult and time consuming for them to carry out the work. That’ll blow out your budget and your timelines.
If you’re a home owner, your roof pitch also has a bearing on the ease with which you can access your own roof safely to check and maintain it. A steeper roof pitch means potential access difficulties and thereby increases the chances that you might not detect roofing and drainage problems before they become entrenched and expensive.
Roof weight
Because roof pitch affects and limits the range of roofing materials open to you, it also has a flow-on effect when it comes to the projected weight of the roof. That translates to careful consideration as to the structure that needs to be in place to support the weight. Again, this can affect the overall design of your property, including room configuration, and can severely limit your ability to reconfigure the floorplan or remove walls if renovating.
Learn more about potential issues with the ceiling cavity/interior roof and roof exterior.
Roof pitch and solar panels
Being able to accurately calculate roof pitch is also important when it comes to installing solar panelling. Your solar panelling is manufactured to perform optimally when installed at a particular angle.
Solar panels
Solar panels are a brilliant way to lessen your power bills and increase you energy efficiency. If you are planning on installing solar panels, you need to consider whether or not the roof on the home you’re inspecting will accommodate the panels you need.
The angle that your solar panels are mounted on will affect the amount of power they provide. Standard roof pitches in Australia are usually either 15 degrees or 22.5 degrees, depending on the materials used in the roof. The incorrect roof pitch and panel angle will mean that the panels won’t be able to self-clean in the rain, meaning that you’ll have to manually clean them more often and the panels may not be effective if incorrectly installed.
Calculating the best tilt for the panels you need on your roof is pretty simple – you just need to know the latitude where you live. Here’s a handy table to show you the different optimum tilts for every major Australian city.
City Latitude/Degree
Darwin 12
Brisbane 27
Perth 31
Sydney 34
Canberra 35
Adelaide 35
Melbourne 37
Hobart 42
How to calculate roof pitch
You can most accurately calculate roof pitch from inside the roof space, with reference to the internal supporting structures of the roof comprised of the rafters and joists as well as an imaginary vertical line drawn up from a point directly under the roof ridge.
Imagine you’re looking at an internal cross section of the roof. To calculate the pitch of a particular section of the roof, you need to picture that section of roof as a right-angled triangle. A right-angled triangle is made up of three sides: the opposite side, the adjacent side and the hypotenuse. The slope of the roof (which is diagonally across from the 90° angle) is the hypotenuse of the triangle. The horizontal side of the triangle is the ‘run’, also known as the ‘adjacent’ side and the side of the triangle that rises up vertically is the ‘rise’, or ‘opposite’ side.
If you don’t know the length of the hypotenuse, you can find it out by using Pythagorean Theorum, an equation that uses the rise and the run.
You then need to plug these figures into the correct sine, cosine or tan mathematical equation to calculate roof pitch. And this is where the wheels come off for most of us!
How it can all go pear-shaped when you calculate roof pitch
One of the most common mistakes you can make when you calculate roof pitch is to choose the wrong equation. For that very reason, we’ve developed a roof pitch calculator to take the pain out of trying to figure it out. You only need enter the measurements for the rise and run and we’ll take care of the rest, giving you the peace of mind of an accurate calculation every time.
That aside, if the person who built your property didn’t calculate properly and you’re seeing the tell-tale signs of roof pitch problems, you need to act quickly. Contact us at Action Property Inspections today on 1800 642 465. We’ll send a friendly, experienced and professional building inspector your way to compile a comprehensive building inspection report and give you advice as to your options.
Buying a home with some DIY Renovations? Book an inspection now.