Restoring an old cottage...

Tag: breathable walls

Walls on Top of Walls

The room that will become our bathroom is on the first floor of the Victorian stone portion of the house. The stone walls have been lime plastered in the past, patched with gypsum plaster, and then skimmed with gypsum, painted, wallpapered, painted again, and generally added to over the years.

As we’ve taken layers of wallpaper and paint off, we’ve had a bit of a conundrum: plaster has come off in places too, which is pretty common in old houses. Plus the tops of the walls, where they disappear into the ceiling, were a right mess.

Old walls with plaster crumbling

Messy messy walls

What to do?

Do we patch the holes and skim over?

Pull all the plaster off and start again from scratch, filling in all the big holes?

Or do we build a new set of walls inside the old walls, leaving the surfaces as-is, and have a more-or-less square room?

Vicky was in favour of pulling the whole lot off and starting again; Joe was in favour of building a framework inside the walls.

In the end, when faced with the magnitude—and dusty mess—of basically pulling down the walls, we decided to batten the walls and put up wood-wool panels ready to take lime plaster.

Battens going into the wall to hold the wood-wool panels

Battens going into the wall to hold the wood-wool panels

Our main concern was losing too much room area by effectively bringing in all the walls by a couple of inches each—but it’s a large room.

How We Did It

We bought a whole bunch of 38 x 18 mm battens from B&Q, and fastened them to the walls as a frame. We measured the frame so that the wood-wool panels from Ty-Mawr would fit neatly to them.

This was actually a monumental pain in the butt because it involved masonry drills and not really knowing whether or not any of our plans would actually work…

Writing on wall reads: Vicky + Joe made this bathroom Winter 2021. It was both fun and a right pain in the arse. S0 WHY HAVE U TAKEN OUR WALLS DOWN?

We really did have a right old time with this

We piloted through the battens to prevent them splitting, then used a masonry drill bit to put holes through the plaster and into the solid stone of the wall.

This proved super-irritating because quite often we’d miss a stone, or it would shift, or the gods of renovations would just be in a bad mood that day. It was a trying time.

Once the holes were drilled, though, we screwed the battens into the walls using 120mm concrete screws. That frame is solid as a very solid thing.

We were genuinely worried we were not going to be able to find anything to work on those walls, and that we would end up having to pull all the wall surfacing down and start again. Thankfully, though, the screws held and we were able to start fixing the wood-wool panels thusly:

Wall, battens, and the first wood-wool panel screwed into the bottom of the wall

First panel goes on

These lining panels are simply screwed into the battens using wood screws and big plastic washers to spread the load and prevent the screws being pulled through the panel. They’ll take lime plaster beautifully. The room already looks vastly different:

Room’s looking swish and ready for plastering

Room’s looking swish and ready for plastering

Looking much tidier

Looking much tidier

One of things we’re pleased with is the main window, which was a right mess. The window “ceiling” was pretty much open to the eaves and we were losing loads of heat, so we stuffed a bunch of insulation up there, then built a mini-frame with battens to hold the wood-wool. We had to make wedges because the window slopes backwards, and we needed to leave as much of the oak windowframe visible as possible to allow as much light in as we could:

IMG_6482

Then we fixed the wood-wool panels and now a multitude of horrors are hidden, the wind no longer whistles in, and it’s tidy tidy tidy:

Fully paneled window return

Look at that! Out of sight, out of mind…

We’re pretty chuffed with the result and we’re excited to see how the plastering goes.

The room still feels pretty large for a bathroom, it’s much warmer, much more soundproof, and it’s definitely going to be easier to work with.

We’re getting quotes for plastering to be done for us because we don’t fancy plastering the ceiling and dealing with the loft hatch. The plan is to have softly rounded plaster around the window frames, and oak windowsills, which we’ll need to install before any plastering is done.

Then we’ll be creating a waterproof shower cubicle by building a stud wall and lining it with specialist tiling wall panels and a ceiling panel that are all fully waterproof—then tiling it.

More on that next week…

Oh—and also!

Ken came along and built us a new doorframe:

A wonky old doorframe made from bits of crappy leftover wood scraps

Before: wonky and saggy

New oak doorframe

After: beautiful wonky oak doorframe

You may be wondering why we didn’t just straighten up the top of the doorframe. Which is a reasonable question.

You can see the stonework above the doorframe—there was no proper stone lintel, and we didn’t fancy taking out that structural stonework to make the doorway higher. And to level it below the stone would mean an extremely low doorway for Joe to limbo through. So wonky it remains. Much like the rest of the house.

Then we had a quote for an oak door from the guy who does our windows (who is amazing) and we laughed and laughed and decided a summer project for us would be to make our own oak door because how hard can it be?

Moisture Management in Old Houses

Old houses are not the same as modern houses, and we can’t treat them the same way.

They’re designed to breathe and when they’re treated well, damp isn’t a problem.

Ancient buildings like this one don’t have a damp course in the walls to stop moisture being sucked out of the ground and into the walls. They also don’t have an air cavity in the walls to stop water transmission from rain on the outside surfaces to inside the house. Often there’s an oak frame that really does not mind getting wet as long as it has a chance to dry out afterwards.

Newly plastered wall panel

You can see the damp on the old brick panels

It’s really important to think about moisture management in an old house like ours.

It’s tempting to make efforts to stop the movement and transmission of this moisture altogether. Here’s some stuff people do to old houses to try to accomplish this:

  • Using modern waterproof grout to repoint all the stonework.
  • Laying a concrete slab under the ground floor
  • Using modern renders on the walls, internally or externally, to stop water moving around.
  • Painting with modern plastic paints.
  • Getting a damp-proof company in to inject the stonework with oily stuff to act as a damp course (many of these companies are absolute vandals when it comes to old buildings).
  • Pulling out original frame panelling and replacing it with modern bricks and mortar.

We found a lot of this stuff in The Dingle when we got stuck in, and it’s really common in old houses that have been “improved”. The problems are, though, that:

  • The concrete slab pushes water up the walls.
  • The modern grout traps water next to the stone. Cement grout is harder than the stone itself, so when the water freezes in cold weather, it puts pressure on the original stones and cracks them.
  • The new render on the outside of the house traps water against the frame and panels causing the frame to rot.
  • The brick infill panels trap water against the oak, ensuring it never dries out.
  • Internally, water vapour from breathing, cooking, and bathrooms is trapped inside, causing the walls to become permanently damp and develop mould.

All that well-intentioned effort makes such a house a horrible damp place to live, and eventually destroys the building.

So here is where we need to talk a little about lime and its purpose in an old house like The Dingle.

We can use lime as a mortar between stones and brickwork, and as a plaster to cover the stonework or anything else your walls might be made of. Lime is magical:

  • Lime is waterproof in that it soaks up moisture, and then releases it to the atmosphere.
  • Lime wicks water away from timber or stones and allows it to evaporate away.
  • Lime has natural anti-fungal properties and does not allow mould to grow.
  • Lime is a little bit flexible and does not crack easily.

Lime was essential in building a house like this one. If we remove the lime and replace it with cheaper modern equivalents, we will wreck the house. Stones will split, timbers will rot, walls will grow mould.

Modern materials are fine for modern houses, which are designed to be airtight and watertight. They are not fine for old houses.

If you own an old house and a tradesperson is talking about using modern mortar, plastic, concrete, modern paint… please please please think very hard before going ahead.

Get advice from someone who specialises in working with old buildings.

If you try to shoehorn modern methods into old houses, you could well be doing huge damage to your home.

© 2022 Project Dingle

Theme by Anders NorénUp ↑