Tag Archives: roof

The bathroom fan debacle

I completed this project a while back and had the images saved up for a blog post – somehow almost a year has gone by since then in a blink of an eye. But anyway, enjoy this delayed update about the exciting world of bathroom fans!

If our house had one deficiency, it would be that the layout of the property has resulted in a rather small and interior only bathroom. Since this bathroom has no direct access to any outside walls for easy ventilation via windows, it instead had a pretty chunky fan already installed when we purchased the property to extract all the shower moisture and other undesirable elements.

By my estimation, the fan would be a good 20 years old and whilst it was doing a good job of extracting air from the bathroom it had two major issues:

  1. Whilst it extracted air successfully from the bathroom, it didn’t send it anywhere useful – instead it was dumping all the moisture directly into the attic space making the attic (and by extension, the whole house) damp.
  2. The bathroom roof features a large skylight which is great for making the room feel light and more spacious than it actually is, but it also acts as a giant shower dome, with steam going up into the skylight space and condensing as the fan is not at the highest point of the roof.

The second issue above really started causing significant issues, particularly since the moisture was damaging the paint and plasterboard and with a small bathroom that makes it almost impossible to extend a ladder and reach the super high ceilings, mould was becoming an issue due to inability to access to tackle the moisture.


The situation required remedial work and one day the old fan decided to make the decision easy with the fan cover getting brittle enough that it suddenly fell out of the roof into the bath one evening without warning with a loud crash.

Unscheduled rapid disassembly


For this replacement project, I started with tackling the ventilation problem to make sure the air would actually get extracted out of the house, rather than into the attic (side note: pretty sure venting bathrooms into attics is now forbidden under the building codes for any new installs).

To do this, I brought a 150mm Simx/Manrose Thru Roof Cowl Kit – these can be found at consumer hardware stores and it’s a kit that consists of a plastic tube, the metal cowl ontop and a suitable rubber mounting boot and assorted hardware.

Going through the roof was the only option on this property. Not only is the bathroom in the middle of the house, even if I ran a long ducting run to the nearest walls, there’s no soffits or other tidy location to install the vent without damaging the character of the property.

Who cares about the iPhone, *this* is the unboxing you’ve been holding out for.

Installing this was… fun. I purchased my new most-favourite-thing-ever, a reciprocating saw (also called a sabre saw) in order to cut a hole in the roof. This tool has gone on to work hard in a large number of other projects and I consider it an extremely good investment given it’s versatility.

Cut all the things!

One of the quirks of our property being approximately 100 years old is that the roof is sarked with timbers which makes it extremely solid – a proper house, from a more refined age. They stopped building houses like this a long time ago, I think the whole non-sustainable forestry part become a slight issue…

In this situation the solid build both helped and hindered – trying to cut through corrugated iron is a lot easier when there’s not 20mm of native hardwood underneath it as the saw has the habit of picking up the iron and vibrating it like crazy whilst trying to cut the timbers.

But the upside is that it meant I could screw the roof vent directly into the timber and be assured of a tight and long-lasting fit, whereas if I had only floating iron sheets it would have been a lot tricker to get a really tight fit… If this had been the case like in a more modern property, I’d have probably brought some plywood sheets and run them across the rafters to provide a solid surface for screwing the vent into for a similar effect.

You can get an idea of how solid the house is from this photo inside the attic. In this photo the vent has been installed and ducting attached.

Once I cut the roof hole, I sealed the vent kit rubber boot thoroughly with silicone, with a layer between the boot and the iron sheets, as well as around the edge of the boot and the plastic tube.

The rubber boot has a metal strip allowing it to be bent to fit the corrugated iron snugly. Once the screws went in, it’s a very tight seal and the silicone makes 100% sure it’s sealed.

Note the diagonal placement – this is intentional since it ensures you don’t end up with a pool of water collecting at the top of the boot, which could happen if you placed it square.

The new vent next to the bathroom skylight. You can see the interior intake through the skylight.

You’ll notice that I’ve cut the hole overlapping two separate sheets. This… isn’t ideal, I’d much rather have cut into a single sheet (easier to seal, less to go wrong as the sheets expand and contract) but I was trying to utilise an existing hole that was already cut in the sarking timbers for what must have been a small vent (maybe an overflow pipe?) in the past to minimise the amount of cutting needed.

This placement also caused another small annoyance for me, which is that the vent is not quite 100% straight and you can notice it sometimes. It’s not an issue for water ingress in the rain, but it annoys me not being 100% perfect. That being said, I’ve had trades install other vents in the property (future project post coming!) and they didn’t get it properly straight either, so I feel somewhat vindicated.

Slightly wonky vent will annoy me everyday forever more…. but if I’ve learnt anything re DIY, don’t fuck with anything that ain’t broke.


To connect the fan to the vent, I brought some insulated ducting. It’s important to use insulated ducting for this, rather than the cheaper uninsulated stuff, since bathroom air is warm and moist – if the ducting is not insulated, you are likely to suffer condensation in the duct as the air cools when it transits through the cooler attic temperatures. By keeping it as warm as possible on it’s way out you can avoid this.

I was worried about some condensation occurring in the vent tube itself – I can’t insulate outside of the roof after all – but this fortunately hasn’t been a problem. Additionally there was some concern that the roof cowl wouldn’t be enough to keep out rain in Wellington winds, but this also hasn’t been an issue – it could be a different situation in more exposed areas of the city and there are cowl fittings that are more suited for unfriendly wind conditions if this was the case.


Next I had to sort out a new fan. I was tempted to keep the existing fan given it’s strong air throughput and the motor still running fine, but I couldn’t easily find a replacement front for it, and the back was completely exposed so there was no easy way to fit the ducting to the back of the fan.

I ended up buying a 250mm “high pressure” fan, but unfortunately this didn’t work out well for me. Despite being described as high pressure, I can confirm that these consumer-available bathroom fans are absolutely useless and not worth buying if you want anything more than a faint breeze.

I had it in place for 1 week, during which time we not only quickly noticed it struggling to remove the steam from the room, but that it was also slowing filling up with water that was condensing in the fan as it struggled the clear the room.

First iteration. Note the side exiting fan which required twisted ducting – not ideal. You can also see the hole in the sarking is larger than needed – that’s because there was a pre-existing hole that I took advantage of which was longer than I needed.

Unfortunately given how much of a complete failure this fan had been, I had to remove it and find an alternative.


The solution was a 150mm pro-series Simix inline fan capable of delivering 166l/s (597m3/hr) air throughput. For comparison, the previous attempted fan was maybe 69l/s (250m3/hr) at best and even that seems dubious given how poorly it performed.

Nimbus is a big fan of this model.

I couldn’t find these at any consumer hardware store and ended up taking advantage of a friend with an electrical trade account who was able to place an order with the supplier for me.

The one key difference with this solution vs my previous attempt is that the fan is inline, which means the bathroom needed a vent installed, with ducting from the intake vent to the fan, then ducting to the outlet vent. This does have some noise advantages since you can place the fan motor further away from the intake.

Second iteration. Mounting it on framing timber is a little overkill but I had framing timber and not plywood handy. Because of the solid roof, I found it easier to mount to the underside of the roof, rather than building a platform on the attic floor.

This solution worked much better – the fan is able to extract a considerable amount of air and whilst a bit noisy due to high RPM and small diameter, it does a good job of clearing the bathroom throughout the shower and not letting it build up too much moisture.

When researching this project, it was suggested  that you shouldn’t be clever and mix duct sizes (eg a 200mm fan into a 150mm vent), so I kept the same spec throughout – if I had gone for a larger roof vent and duct in the beginning, I might have gone with something larger to get more throughput but also larger fans tend to be quieter (as a general rule).

The other big positive of this approach is that I was able to solve the skylight condensing problem by putting the new intake vent directly into the side of the skylight wall to rapidly extract out the air.

This is working extremely well – whilst we have the existing damage from past moisture build up which will require remedial work (complete repaint, maybe some new plastering), since putting in this new vent we’ve had very little moisture build up since the fan keeps the air moving in the skylight preventing condensation. And since heat rises, all the steam from the shower naturally gravitates towards the vent anyway.

This photo illustrates the issue with the placement of the old vs new fan – the old one did nothing for all the stream that wafted up into the skylight space, vs the new one keeping that space clear.

I found it really hard to find an intake vent that wasn’t horribly ugly and plasticky, so ended up paying a bit of a premium for an aluminium model. It ended up being a right pain to install so maybe I should have gone for a cheap nasty plastic 150mm that would have been simple to fit, but I think it was worth it and looks good (once I fix all the paintwork anyway). I even managed to get it dead centre which given I was cutting it out from inside the attic due to inability to get ladder high enough in the bathroom was a pretty good outcome.


Anyway despite the challenges, I’m pretty happy with this setup now. It’s working reliably, I’ve checked the ducting a few times to make sure there’s been no moisture build up or water ingress from outside (both good!) so I’m expecting this solution to last for a long time.

I still need to fix the plasterboard and paint job in the bathroom. It’s kind of stuck pending access to a more flexible ladder/indoor scaffold type system just due to the height of the bathroom roof and very limited placement points for ladders. Still it annoys me daily so it’ll get fixed sooner or later when I get really sick of it looking so bad.

Rough cost for the project was around $500-600 NZD in parts – the most expensive bits being the fan motor, and then the roof vent kit – a wall vent solution would be a fair bit cheaper.

If I was doing this project again from scratch, I’d probably have done a few things differently.

  • I’d almost certainly have considered getting the bigger model and going for a 200mm fan able to shift 272l/s (980m3/hr) of air. The current model is good, but I’d almost have enjoyed the bathroom being like a vacuum cleaner for maximum dryness. And the larger fan size should be a bit quieter.
  • I utilised the existing hardwired appliance circuit as a straight replacement of one fan for another, but it would have been good to get a timer fan installed, to keep it running for a given time period following the fan being switched off. This is something I might end up getting an electrician to install for me in future anyway, but I might have been able to save some money getting a model of fan with the timer circuit build in, vs having to now buy a timer module for the circuit.
  • I don’t love the ducting install. I ended up with two 90 degree bends which were unavoidable due to the original hole being intended for a fan directly below the hole, but I’d have preferred an almost straight run to ensure minimal workload for the fan (maybe some noise reduction too?). This could have been easily accomplished by installing the fan further up the roof line and running the duct straight from the interior vent, through the fan, then up and out the roof. But it wasn’t worth sealing one hole and cutting another to fix.
  • If I ever build a house, I’m making sure the bathrooms have at least one exterior wall to make ventilation so much simpler!
  • I put in all the vent bolts (hex head) using an automotive socket set by hand. This works totally fine but just takes ages, so an impact driver would have been a nice addition to the tool kit. That being said, I’ve since done other hex head screws using a socket adaptor drill bit which allows me to use the cordless drill to drive hex head screws, although admittedly lacking the high torque of a proper impact driver.

10 months in

It’s been almost 10 months since Lisa and I brought our current house and moved in. Things are going well, having our own place and not paying a landlord is a fantastic and freeing feeling, but home ownership certainly isn’t a free ride and the amount of work it generates is quite incredible.

So what’s been happening around Carr Manor since we moved in?

Home sweet home

Can’t beat Wellington on a good day!

Generally the house is in good shape, most of my time has been spent in the grounds of the estate clearing paths, overgrown vegetation and various other missions. However we have had a couple smaller issues with the house itself.


The most serious one is that part of the iron roof in the house was leaking due to what looks like a number of different patch jobs combined with a nice unhealthy dose of rust.

Hmm cracks in the roof that let water in == bad right?

Hmm cracks in the roof that let water in == bad right?

The outside doesn't look a whole lot better.

The outside doesn’t look a whole lot better.

The “proper” fix is that this section of roof needs replacing at some point as it’s technically well-past EOL, but roof replacement is expensive and a PITA, so I’ve fixed the issue by stripped off as much rust as I could and then re-sealing the roof using Mineral Brush-On Underbody Seal.

Incase you’re wondering, yes, the same stuff that you can use on cars. It’s basically liquid tar, completely waterproof and ever so wonderful at sealing leaky roofs. I liberally applied a few cans over flashings, patches and the iron itself getting a nice thick seal.



The same stuff did wonders on the rusted shed roof flashing as well.

The same stuff did wonders on the rusted shed roof flashing as well.

Up next I need to complete a repaint of both sheds and the house roof. I’m probably going to do a small job in whatever colour I have lying around for the worst part of the roof and then go over the whole roof again at a later stage when we decide on a colour for the full repaint.


The other issue we had was that one of the window hinges had rusted out leaving us with a window that wouldn’t open/close properly.

So rusty :-/

I’m not expert, but I don’t think hinges are supposed to look like this….

This was a tricky one to fix – the hinge and the screws were so rusted out I couldn’t even remove them, in the end I removed the window simply by tearing the hinge apart when I pulled on it leaving a shower of rust and more disturbingly, cockroaches that had been living amongst the bubbled rust.

This left me with two parts of metal hinge stuck in the wall and on the window frame held in by screws that would no longer turn – or in some cases, even lacked heads entirely.

To get them out, I put a very small drill bit into the electric drill and drilled out the screw right down the middle of it. It’s pretty straightforwards once you get it going, but it was a bit tricky to get started – I ended up using the smallest bit I had to make a pilot hole/groove in the screw head, and then upsized the bit to drill in through the screw. Once done, the metal remains tend to just fall out and come out with a little prodding.

I’ve since replaced it with a shiny new hinge and stainless steel screws which should last a lot longer than their predecessors.

Shiny new

Shiny new hardware


Painting has been an “interesting” learning experience, I’ve found it the hardest skill to pickup since it’s just so time consuming and you have to take such extreme care to avoid dripping any paint on other surfaces.

One of my earliest painting jobs was doing the lower gate. This gate spends a lot of time in the shade and even in spring was feeling damp and waterlogged and generally wasn’t looking that sharp – especially the fact the bolt was a pile of rust barely holding together.

The rustic delight of unfinished timber.

I’m sure unfinished timber looks great when it’s first built, but the moss dirt and damp doesn’t lead to it aging well.

It's like new!

Much sharper!

Things like the gate take time and need care, but it’s nothing compared to the absolute frustration of painting window frames where a few mm to the wrong side or a stray bristle leads to paint being smeared across the glass.

I did the french doors initially as the paint had peeled and was starting to expose the timber to the elements, some of the putty had even fallen out and needed replacing.

Probably the most frustrating thing I've ever had to do.

Applying painter’s tape to this is one of the most frustrating things I’ve ever had to do :-/

Because I was painting around glass, I applied painter’s tape the whole thing before hand. It took hours, incredibly frustrating and I feel that the end result wasn’t particularly great.

I’ve since found that I can get a pretty tidy result using a sash/trim brush and taking extreme care not to bump the glass, but it is tricky and mistakes do happen. I’m figuring with enough practice I’ll get better at windows… and I have plenty of practice waiting for me with a full house paint job pending. Of course I could pay someone to do it, but at $15k+ for a re-paint, I’m pretty keen to see if I can tackle it myself….


The shed works haven’t proceeded much – I had the noble goal of completely repairing it over summer, but that time just varnished sorting out various other bits and pieces.

On the plus side, thanks to help from one of my colleagues, the shed has been dug out from it’s previously buried state and the rot and damage exposed – next step is to tear off the rotten weatherboards and doors and replace them with new ones, before repainting the whole shed.

Dug out shed

A small 1meter retaining wall would have been more than enough to protect the shed, but instead the earth has ended up piled around it causing it to rot and collapse.


I also had help from dad and toppled the mid-size trees that were in-between the shed and the path. Not only were they blocking out light, but they were also going to be a clear issue to shed and path integrity in the future as they got bigger.

Much tidier!

Much tidier! Just need to fix the shed itself now…

I’m still really keen to get this shed fixed so intend to make a start on measuring and sourcing the timber soon(ish) and maybe taking a few days off work to line up a block of time to really attack and fix it up.


A more pressing issue has been our pathways. We have two long 30-40meter concrete paths, a long ramped one (around 20-30 degree slope) up to the upper street and carpad and another zig-zag path with a mix of ramps and steps heading down to the lower street where the bus stop is.

Both paths are not in the best condition. The lower one requires a complete replacement, it’s probably around 80 years old and the non-reinforced concrete has cracked and shifted all over the place.

The upper one is more structurally intact, but has it’s own share of issues. The first most serious issue is that the steeper upmost end gets incredibly slippery in winter. It seems that although the concrete has been brush-finished whenever it rains, any grip it had just vanishes and it basically becomes a slide.

Jethro vs Autumn

Jethro vs Autumn

Naturally slipping to a broken/leg/face/life isn’t ideal and we’ve been looking at options to fix it. We could convert the steepest bit from a ramp to steps, but steps have their own safety issues and we aren’t keen the lose the ramp as it’s the best way for getting large/heavy items to/from the house.

So a couple months ago I put down some Resene Non-slip Deck & Path which is a tough non-slippery paint product that basically includes a whole heap of sand which turns the smooth concrete path into something more like fine sandpaper.

We weren’t too sure about how good it would be, so we put down a 0.5l strip to test it out on the worst most part of the path.

A/B Testing IRL

A/B Testing IRL

It doesn’t feel that different to brushed concrete in the dry, but in the wet the difference is night & day and you really do feel a bit more attached to the path. We’ll still need to invest in a decent handrail and fence, but this goes a long way towards an elegant fix.

I’ve since brought another 10l and painted the upper portion, essentially all the “good” concrete we have. I thought that it might be too dark but actually it looks very sharp and once we put a new fence up (maybe white picket?) it will look very clean and tidy.

Slick new path!

Old concrete, as good as new! :-)

The other ~30meters down to the house isn’t in such good shape, the surface is quite uneven in places and it’s missing chunks. We have a project to do to repair or replace the rest of it, once done the intention will be to paint the rest of the path in the same colour and it should look and feel great.


All this work requires a fair few tools, I’ve finally clean up the dining room where they had been accumulating and they’re now living properly in the shed.



One of the most interesting lessons I’ve had so far is that buying decent tools is often far cheaper than hiring tradies to do something for you – generally tools are cheap, even decent ones, but labour is incredibly expensive.


Why yes, that is a hardwood lamppost that I’m chainsawing.

The same thing applies to parts, it’s generally cheaper to just buy a new replacement of something than it is to fix it – I’m used to this from the IT world, but didn’t expect it from IRL.

In our cases, we had a shower mixer that decided to start letting a constant small stream of water through rather than shutting off properly.

Jethro vs Shower

Jethro vs Shower

Taking it apart and even removing it from the wall entirely isn’t too tricky, but I found after removing it all that the issue wasn’t anything trivial like needing a new o-ring and had to call out the plumbers.

Plumbers took it out, look at and it and are all “yeah that needs a new part”, so I ended up paying for the part + the labour – I’d have been better off just buying the whole new part myself and fitting it rather than trying to fix it.


Never underestimate the amount of waste you produce moving into a new place. I filled a skip with 1/3 concrete rubble, 1/3 polystyrene and 1/3 misc waste and there’s still another skip worth of debris around the property, possibly more once I tear all the rotten timber out of the shed.

Polystyrene is my number one enemy right now, almost everything we had shipped to the house when we moved in came with some and it’s crumbly and completely non-recyclable for good measure >:-(.

Where did all this junk come from?

Where did all this junk come from?



Finally on the inside of the house things haven’t progressed much. Lisa has been working on the interior decor and accessories whilst I’ve done exciting things like overseeing the installation of insulation and fixing the loo in the laundry. :-/

Warming sheep fluff!

Warming sheep fluff!

I hate plumbing!

I hate plumbing!

I also had a whole bunch of fun with the locks – when we moved in I had the locksmith change the tumblers, but we’ve since found the locks were pretty worn out and the tail pieces inside started failing, so I had to buy whole new locks and fit them.

Turns out, whole new locks is way cheaper than getting the locksmith out to change the tumblers. If you’re moving into an older place, I’d recommend consider just getting new locks instead since the old ones probably aren’t much good either.

The only downside is that the sizing was slightly different, so I had to do some “creative woodwork” using a drill bit as a file (I didn’t have a file…. or the right size drill bit. A bit dodgy, but worked out OK).

It's not just the IT world where the lack of standards means a bit of hackery to make stuff function.

It’s not just the IT world where the lack of standards means a bit of hackery to make stuff function.

Tidy job at the end of the day!

Tidy job at the end of the day!


A lot of this work has been annoying in that it’s not directly visible as an improvement, but it’s all been important stuff that needed doing. I’m hoping to spend the next few months getting stuck into some of the bigger improvements like fixing the paths, sheds, etc which will be a lot more visible.

Until then, need to make more evenings to just sit back, relax and enjoy having our own place – feels like I’ve been just far too busy lately.

Beer time

Beer time