Highrises made of wood?

[Surrealplaces]

This should bring on some healthy discussion

18 storey tall wood building residence gets final Board go-ahead
http://ubyssey.ca/news/tall-wood-get...?ref=frontpage

[Architype]

They're expecting this to be approved, in spite of the fact that current regulations only allow wood structures to be six stories high. I have seen some six storey wood buildings currently under construction in Vancouver, but this just doesn't seem realistic.

[drew]

Very cool. I would love to see the details associated with the wood structure of this building.

The link explains how the internal stairwell and elevator core will be reinforced concrete. Makes sense - as at 18-storeys, a reasonable size of wood column would not be rigid enough to resist building sway.

[niwell]

I helped do some work on the regulatory amendments to the Ontario Building Code to allow for 6 storey woodframe buildings. Realistically there aren't many reasons aside from the idea that "wood burns" that would make wood highrises unfeasible. They are cheaper than concrete or steel, and actually perform better in seismic situations. At the end of the day, the Building Code is performance driven - you have to meet the minimum requirements regardless of what the building materials are.

In terms of fire protection it's a lot better than you would think. These wouldn't be constructed like a stick-frame home or complex up to 4 storeys. The wooden materials would generally be manufactured panels and heavy beams, both of which are highly fire resistant. In addition they require sprinklers in pretty much every room, and fire-resistant stairwells. I'd worry a LOT more about fire safety in a 4 storey complex that doesn't have these added safety features.

Interestingly enough, the one reason I've heard that some building code experts / engineers wouldn't want to live in a wood building is the potential for noise. Concrete is definitely superior in this respect. They had no concerns about safety.

Also, most of the fire incidents in wood-frame buildings have been during construction. The buildings are very vulnerable during this stage before fire resistant materials and suppression methods have been added.

[Architype]

The concrete cores do help it make sense, but overall it looks boring, just like any other meh highrise. Also, as the link states, "dealing with moisture issues" is a big red flag.

[drew]

^ the interesting bit about this is the construction - not the look.

Plus I imagine the construction costs are being kept at a minimum.

[osirisboy]

Originally Posted by niwell

I helped do some work on the regulatory amendments to the Ontario Building Code to allow for 6 storey woodframe buildings. Realistically there aren't many reasons aside from the idea that "wood burns" that would make wood highrises unfeasible. They are cheaper than concrete or steel, and actually perform better in seismic situations. At the end of the day, the Building Code is performance driven - you have to meet the minimum requirements regardless of what the building materials are.

In terms of fire protection it's a lot better than you would think. These wouldn't be constructed like a stick-frame home or complex up to 4 storeys. The wooden materials would generally be manufactured panels and heavy beams, both of which are highly fire resistant. In addition they require sprinklers in pretty much every room, and fire-resistant stairwells. I'd worry a LOT more about fire safety in a 4 storey complex that doesn't have these added safety features.

Interestingly enough, the one reason I've heard that some building code experts / engineers wouldn't want to live in a wood building is the potential for noise. Concrete is definitely superior in this respect. They had no concerns about safety.

Also, most of the fire incidents in wood-frame buildings have been during construction. The buildings are very vulnerable during this stage before fire resistant materials and suppression methods have been added.

Yea wood burns!! This fire just happened in Surrey

http://www.theprovince.com/news/mass...698/story.html

This was a relatively new building with fire walls and sprinklers. After watching this thing burn on the news I can't even imagine what would happen with an 18 storey wood building

[niwell]

Originally Posted by osirisboy

Yea wood burns!! This fire just happened in Surrey

http://www.theprovince.com/news/mass...698/story.html

This was a relatively new building with fire walls and sprinklers. After watching this thing burn on the news I can't even imagine what would happen with an 18 storey wood building

That's a 4 storey building (well, looks like five but almost guarantee one is a "basement" or an extended mezzanine space) that is most likely stick-frame construction. They burn much easier, but still slow enough to allow everyone to escape of course. A wood highrise would most likely be built out of manufactured wood panels and large beams, which are much more fire resistant.

Also, I don't remember the exact details but I believe Ontario's Building Code requires sprinklers on balconies and attic spaces on wood buildings 5 storeys or more. This fire spread from the balcony to the attic space.

[HomeInMyShoes]

I believe this will be approved and we will all look back when the first one of the 10+ story buildings goes up in flames and think "what the heck were we thinking."

It's not a question of fire resistance, it is a question as to what is going to happen when it hits flashpoint. We may get what we think is enough time, but it takes a while to get everyone out of a ten story building.

[niwell]

Originally Posted by HomeInMyShoes

I believe this will be approved and we will all look back when the first one of the 10+ story buildings goes up in flames and think "what the heck were we thinking."

It's not a question of fire resistance, it is a question as to what is going to happen when it hits flashpoint. We may get what we think is enough time, but it takes a while to get everyone out of a ten story building.

I've seen the results of fire tests on timber beams and they don't really burn. The outside gets charred but structural integrity is maintained. Moreso than a light steel structure in a similar fire which will begin to deform. Heavy timber beams are actually approved as a material for certain components in the National Model Building Code.

It's all about the type of wood we are building these out of. We aren't talking about 2x4s and sheet plywood, although a stack of fire-retardant treated 2x4s doesn't burn too quickly either.


This is what the frame of a wood highrise could look like:


src:http://thoughts.arup.com/post/detail...oden-high-rise

[osirisboy]

That looks like it would be expense to fabricate the materials. Would reinforced concrete just be easier/cheaper/safer in the end?

[Architype]

Originally Posted by niwell

I've seen the results of fire tests on timber beams and they don't really burn. The outside gets charred but structural integrity is maintained. Moreso than a light steel structure in a similar fire which will begin to deform. Heavy timber beams are actually approved as a material for certain components in the National Model Building Code.

It's all about the type of wood we are building these out of. We aren't talking about 2x4s and sheet plywood, although a stack of fire-retardant treated 2x4s doesn't burn too quickly either.


This is what the frame of a wood highrise could look like:


src:http://thoughts.arup.com/post/detail...oden-high-rise

It reminds me of toys I had when I was a kid. This construction technology is quite different from conventional wood frame construction, but has yet to be proven as suitable for highrise construction.

[niwell]

Originally Posted by osirisboy

That looks like it would be expense to fabricate the materials. Would reinforced concrete just be easier/cheaper/safer in the end?

That particular frame looks to involve some crazy engineering so I'm not too sure. But the figures estimated by the building industry for wood frame construction using prefab fire-retardent panels and heavy timber beams is around 10% cheaper than concrete or steel construction. In Ontario the figure may be less due to the requirement of non-combustible materials for exit stairwells.

One of the big advantages is actually ease of construction, particularly in a tight infill setting. When you can truck in pre-fab components as opposed to pouring concrete etc it's much quicker and less disruptive to the surrounding neighbourhood.

[mattpa]

i my self hate wood but japan does it and they work with earthquakes. construction for trades is easier with concrete cause you can run anywhere wood you need to land on a stud

[Symz]

Remember that old movie Towering Inferno? That's what I think of it.

[TorontoDrew]

It obviously not a good choice for high rise construction if we're only just getting an 18 floor building now. It's a novelty. No matter how earthquake and fireproof it may be soundproofing will be an issue. If your going to make an 18 storey wood statement at least make it pretty.

[Pinion]

Originally Posted by Architype

They're expecting this to be approved, in spite of the fact that current regulations only allow wood structures to be six stories high. I have seen some six storey wood buildings currently under construction in Vancouver, but this just doesn't seem realistic.

Some is an understatement. My area has seen countless six storey woodframes in the last 5 years or so. e.g. The Shore, almost four hundred units of wood condos by itself:

The Shore, North Vancouver by chrisjohann, on Flickr

They pop up so fast.

In my building, my sliding glass shower door won't stay shut in the winter because the walls shift so much. Can't say I'm a fan.

[SkydivePilot]

Originally Posted by osirisboy

Yea wood burns!! This fire just happened in Surrey

http://www.theprovince.com/news/mass...698/story.html

This was a relatively new building with fire walls and sprinklers. After watching this thing burn on the news I can't even imagine what would happen with an 18 storey wood building

That would make for a wonderful updated version of the movie: "The Towering Inferno." Lol!!!

[mistercorporate]

Originally Posted by Pinion

Some is an understatement. My area has seen countless six storey woodframes in the last 5 years or so. e.g. The Shore, almost four hundred units of wood condos by itself:

They pop up so fast.

In my building, my sliding glass shower door won't stay shut in the winter because the walls shift so much. Can't say I'm a fan.

That is a beautiful midrise!! I'd take some of that to break up the monotony of concrete/glass any day!

[cornholio]

I cant help but remember this when they are talking about a 18 story wood building.
• Video Link

I hope this wont be a future lesson.