Checked and updated on January 17, 2021 by Aaron Barnett
Your roof is one of the most important parts of your property so if you’re considering a replacement, the general rule of thumb is that it’s better to be safe than sorry. If you’re unsure whether a replacement is needed (or worth the investment) take note of some of the most urgent and unavoidable signs and reasons. These include:
- Obvious leaks: Seen inside, or inside the roof space
- Water damage: To the roof or wall framing
- Damaged flashings: That are missing or coming loose
- Inadequate roof pitch: For snow to slide off, or water to drain
- General aesthetics: And property value reduction
- Other serious warning signs: Include missing shingles, mold, moss, or fungi and drooping or sagging in your roof.
Re-roofing means, Replacing your roof with a completely new one. You should weigh up the costs of re-roofing your house completely or doing a repair instead in the vital area in need, and maybe a full roof paint job.
Roof damage: The most common reasons
There are several factors that can contribute to a faulty roof. The most common include:
- Rusting fixings: Screws are rusting from being incomparable with the roofing metal or environment
- Failing flashings: That no longer protect high-risk corners from water penetrating
- 1. Rusting roof material: Fixings like screws might be causing your metal roofing to rust (Only replace the fixings and fast! before it’s too late)
- 2. Rusting roof material: The cut edges have no rust protection, instead only surface protection as seen on older roofs around the ocean.
- 3. Rusting roof material: The chosen roofing material was not adequate for the location and levels of salt in the air
- 4. Rusting roof material: General age and wear and tear, makes it time for a roof replacement
- Building movement: Low pitch membrane roofs on a building that has moved and dropped in a corner may no longer drain correctly
When to repair your roof?
In some cases, you don’t need to replace your whole roof, you can do a repair of a leak, fix a flashing, or do a full sandblast and repaint.
If your roof doesn’t have any major problems but is just in the need of a visual touch up you could consider sandblasting the old surface and spraying on a new coat of paint.
However, you should consider the cost of hiring and setting up a scaffold, corrugated roofing material is pretty cheap, and fast to install. If a high and complicated scaffold is required, consents are needed, and tradespeople have been organized, it might make sense to do a full re-roof in one go.
If you’re wondering? can you replace only half a roof or a portion? of course, you can. You want to again consider the setup costs such as scaffolding, consents, and getting the right roofers on the job. To weigh up if spending a little more to do a full re-roof is better in the long run.
How long should different roofing materials last
Roofing materials last differently depending on the environment you are in. If you are close to the sea you need higher levels of corrosion resistance.
With that being said, there is an estimated lifespan for different roofing materials and how long they should last in a standard environment.
- Thatched straw roof – Ther are a few different design types but between 10-15 years if there is a ridge, and upto 25 years depending on the design
- Membrane roof – 10 – 50 years depending on the setting
- Asphalt shingles – 15-30 years
- Galvanized steel roofing – As a surface layer protection only cut edges will corrode especially around the sea, but away from a marine environment, it can last 40 years.
- Zincalume or galvalume roof – Is designed to last 4 times longer than galvanized steel roofing as the protection is mixed into the metal. Most manufactures have a 36-year guaranty. But designed for 50+ years, but not being the best roofing around the ocean.
- Tin roofing – Averages at 50 years
- Aluminum roofing – Has an average life span of 50 years
- Copper roofing – Can last 50-100 years even around the sea
- Zinc roofing – Can last between 60-100 years around the sea
- Cedar shingles – Can last 50 years but weathers fast
- Concrete tiles- Up to 100-150 years
- Slate tiles – 125-200 years
When is it worth replacing your roof?
For your own safety, if your roof is displaying any of the above signs, you should replace a roof before water damage like mold or rot has the chance to damage the timber framing.
Not only is this hazardous to your health and safety, but the repairs may end up being more costly than replacing your roof before the damage occurs.
If you’re considering selling your home, it’s also worth replacing your roof before putting it on the market; not only will a replacement make your property more appealing but it’s likely to stop the problem from massively decreasing your property value.
It might also be a good idea to do an early roofing replacement by installing a longer-lasting roofing material, before a solar panel installation, if the current roof would need to be replaced in the near future.
Will replacing your roof increase your property value?
Replacing your roof is a great way to increase your property value. Not only can it enhance the structural integrity of your property, but it can also increase its selling price and time too.
According to research by thisismoney.co.uk, replacing your old roof can weld a return on your investment by 63%.
When is the best time to replace a roof?
If you’ve decided to replace your roof, the weather is an important factor to consider. Ideally, you should carry out the work in the drier months as rain and cold weather can slow down the process.
This is frustrating from a financial and personal perspective as a slow repair will require more plastic coverings to prevent water damage which can be costly.
Also increased time to do the job will increase scaffold hiring costs if needed. This is why it can be better to get a team of experts that can get the job done as quickly as possible.
It’s not really a DIY job if you’re replacing a whole roof unless you have the experience, and experienced hands to help you.
What’s the best type of roofing?
#1 Corrugated iron
Pros:
- Cheap and fast to install
- Durable and doesn’t deteriorate quickly
- Many different designs and colors and durability options with thickness and rust protection properties
- Green alternative to some materials helps reduce your carbon footprint
- Lightweight, and reduced the framing requirements for your roof.
- With a good roof pitch, and eaves its a low-risk roofing in terms of weather tightness
- Sounds good when it rains
- Easy to install solar panels on top
Cons:
- Some people prefer a different look
- The roof needs to be at least the minimum draining pitch
Roof tiles
Pros:
- Long-lasting – some last over 100 years
- Heavy thermal mass makes them energy efficient
- An array of options to match your style
- Can increases property value on large estates
Cons:
- Can be expensive
- Can break easily with heavy impact
- Not suited to all roof slopes
- Extra framing support is required for the extra weight
- It might be better to spend the money inside instead.
- Not good in an earthquake compared to lightweight materials
Shingle roof
Pros:
- Different types to choose from (e.g asphalt, cedar, metal), can match various home styles
- Affordable
- If cedar is chosen it could make a for a good feature on a small but steep roof. Or as a cladding material on a gable end.
Cons:
- Some types like cedar can be expensive and slow to install
- Not always easy to maintain
- Damages very easily
- Asphalt tiles due to there small life span are filling up the US dumps making them bad for the environment.
Membrane roofing
Pros:
- Damage is easy to repair
- Your roof pitch can be very minimal if you want to build up, but have a building height limitation from neighboring properties
- The roof can be close to flat making it safer to work and do maintenance on
Cons:
- Can be tricky to find an installer
- Obstacles on your roof (e.g chimneys) can make installation difficult
- Really does looks ugly
- Can be slowly leaking without you knowing
- Water doesn’t quickly drain away as it does on metal roofing
Factors to consider if your house is close to the sea
If you live close to the beach, there are several things you need to consider before replacing your roof. To prevent rusting, it’s worth investing in some corrosive resistant materials like copper or Zinc to prevent damage and increase your roofs life span.
You should also be sure to opt for materials that can resist wind-uplift; materials like standing-seam metal are a reliable choice for tough conditions.
Galvanized steel is generally not recommended for coastal homes due to its vulnerability to weathering; salt air can eat through the material quickly and leave you with an expensive repair bill.
You also need to make sure that different materials i.e your primary roofing material and your screws and other fixings are compatible. Read more below on picking the right roofer.
When to DIY a roof replacement job
If you have the skills and the tools for the job, there’s no reason why you can’t attempt to perform your own roof replacement.
However, you should make sure you plan your repairs extensively and perform them safely for the protection of yourself and your property. Just check with your local law and get the required consents of what you can and cannot do.
For a single leak in your roof, have a look as you might only need a pair of tin snips and a tape measure. Measure up a new flashing, take the design to your local roofing specialists, and get it made, just ask them to change your design for the required laps and angles required for the building code.
Before you get started have a look at the best sheet metal cutting tools as recommended here.
When to get a qualified roofing team to replace your roof
If you want to replace your roof, it’s not always possible to do the job yourself and you may require professionals to complete the installation. Some reasons that may require you to seek a professional installer include:
- If the installation is too complex for you
- If a building consent is required
- If you need the job completed as quickly as possible
- If complicated flashings are required
- If you require scaffolding
When getting a professional to replace or repair your roof, it’s important to get someone trusted, don’t go for the cheapest price, but a company that has been in the business for a long time and has a reputation they care about.
Things can go wrong with roofs, it’s really is a job that requires a lot of skill and is undervalued by many.
Complicated roofs require many flashings that are not easy to measure, design, cut, and install. Simple roofs however can be much easier but even still many builders subcontract roofing jobs to roofing specialists to cover this big part of a building job.
Avoid being ripped off | Picking a good roofer
Before choosing a roofer, know how to spot and pick a good roofing specialist. While steering clear of churn and burn roofing business. A good roofing professional will be an expert on different metals and their compatibilities within different environments. They use pro brand tools and don’t take cowboy shortcuts.
Does your roofer understand what causes corrosion
There is a lot to know about how different metals react when mixed with other materials and the environment. The reason for this is different surfaces of metal have different levels of conductivity. If two surfaces of metal touch directly or with a bridge of water, it creates a path that electrons can travel.
During this movement of electrons comes the deterioration of metals or what’s known as corrosion or rust.
Electrons will move to the material with the highest level of electrical conductivity and this is the piece of metal that will corrode first. The bigger the conductive difference the more this will happen and the faster rust will occur.
Often this can be worked out just by what type of metals are being used together or mixed. But not only does the type of metal have an effect here but also the total mass of each metal type.
This makes it important to be careful when mixing metal types and should be avoided altogether when possible. But sometimes mixing metals for your roof is required to keep costs down, Buts it’s important the metal types chosen are taken into full consideration.
For example, you don’t want a roofer to install fixings in your roofing material that are not compatible and will cause one material to rust out too soon. This is why it’s important to pick a good roofer that is an expert on metal compatibilities.
You want a roof that is designed to protect your primary roofing material while having all metals close to the same level of conductivity to reduce the speed of corrosion.
Have you chosen a roofer that will actually fix a leak
After taking metal types into consideration make sure your roofer has actually designed metal flashings made from the correct materials for your environment to fix a leak.
If you get a roofer that uses only flashing tape to fix a leaking roof, this should only be a temporary fix to stop immediate water damage. Otherwise, its a cowboy move.
Flashing tapes are only supposed to be used as secondary water protection underneath the primary defense of a wall cladding or roofing material. At the same time, these flashing tapes react with some metals. Flashing tapes will melt and degrade in the sun pretty quickly and you will have the same problem in a few weeks or month’s time.
As a general rule, a new flashing that has failed around the ocean should be replaced with pure zinc or stainless steel for a longer life span.
Client health and safety responsibilities
And as new health and safety rules apply depending on your country if a client pays for a roofer that cuts costs when it comes to safety, not only is the employer liable but also the client that paid for the unsafe work to happen.
Signs you need a builder to reframe your roof
When a roof needs to be reframed, it’s usually because the timber in your roof is rotting, or because the pitch on your existing roof is not steep enough to comply with your new roofing material. Or you want to increase your roof pitch for a more efficient solar panel angle.
If you’re wondering, why does my roof look wavy? You want to get a builder to straighten the roof framing before you install a new roofing material, a wavy roof could be an indication of a leak and rotting timber that is deteriorating and sagging in extreme cases.
Or an up and down roof could be a sign of a sagging and sinking house. But more than likely some timber movement has just occurred over the years, or maybe it was just built that way, a little bit out of wack.
If you have any of these issues with your roof, it is worth contacting a builder to inspect it and assess whether new framing is appropriate.
As well as fixing existing issues with your roof, reframing can also give you more space in your property if you opt for designs that increase the height of your roof.
Checklist before replacing your roof
Before you embark on your installation journey, be check the following things before proceeding:
- Check that your roof does not contain asbestos ( A highly hazardous material, don’t enter your roof space if this is the case)
- Remove items from your attic
- Trim any tree branches that hang near your roof
- Identify power outlets for yourself or your contractors
- Remove antennas or satellite dishes
- Make your neighbors aware of the repairs
- If you’re not performing the repairs, make plans to be away from your home throughout to prevent disruption if needed
- Protect items outside your home such as cars and windows
- Protect your guttering system by using the correct equipment or choosing a contractor who will
Conclusion
You now know when a roof needs to be replaced. The decision of if you should repair a partition of your roof or replace it fully should come down to your desired end result, and what the height access costs are, as you don’t want to pay for this again in your future.
If it’s a big job find a qualified team that can get the job done ASAP, to reduce scaffold hiring costs, and if you only need to order a few sheets of corrugated iron for a full re-roof, do it while the scaffold is paid for and set up.
If you have the skills and the job is within your capabilities make sure you have the correct metal cutting tool for the job.
And of course, take into consideration the essential safety steps for working at dangerous heights.
References:
- Information about membrane roofing, retrieved from, https://build.com.au/roofing-membrane
- Straw roof life spans, retrieved from, https://www.heartofenglandthatchers.com/how-long-should-a-thatch-roof-last-for/
- Rust and how it forms, retrieved from, https://newscenter.lbl.gov/2012/09/06/rust-never-sleeps/
- How rust forms on metal, retrieved from, https://galvanizeit.org/knowledgebase/article/stainless-steel-in-contact-with-galvanized-steel
- Different roofing types and there life span estimations, retrieved from, https://www.roofcostestimator.com/roofing-materials-and-installation-costs/
- Zincalume details retrieved from, https://rosteelroofing.com.au/zincalume-vs-colorbond/
- Return of investment from replacing your roof, retrieved from, https://www.thisismoney.co.uk/money/mortgageshome/article-2834756/Which-home-improvements-add-house-prices-investment.html
My name is Aaron, and welcome to Bangingtoolbox.
As a qualified builder and DIY’er, my goal with Banging Toolbox is to provide the #1 building and DIY resource on the internet for my readers.
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