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Addition foundation and whether to build from basement level

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[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes

Addition foundation and whether to build from basement level

Planning to build an addition in the backyard, and have a couple of decisions need to be made:

1. Whether to have full concrete foundation or concrete piers foundation. First factor is of course the cost. Concrete piers foundation is cheaper with two drawbacks 1) The addition can't be finished with brick to match the house (but stucco/vinyl/aluminium) as those piers can't support the weight of all brick 2) With concrete piers foundation, it meant to be for ground level addition only (so scrap the basement level up idea). By the way, I was watching the youtube video on how they build concrete piers foundation, it is like building the foundation for deck. Will they cover the footing of the piers ? If not, I am worried how durable is this foundation as things can go underneath and the whole platform is just wood.......

2. Whether I should build the addition from the basement level. It will cost more as the contractor will need to dig one level deeper and whole foundation will be full concrete. But I was warned that it will be just like a dark room with one door opening cut from the existing basement foundation. So, I was told that it really depends if I have need for this extra dark room and willing to pay for additional cost. Some contractors say the cost for two levels will be double, but some say it is just $10-15k more for going down basement level, not sure who is right........

What do you guys think ? Thanks for any advice and opinions.
34 replies
Deal Expert
Feb 7, 2017
15498 posts
12708 upvotes
Eastern Ontario
Your RFD Profile under your User Name is missing your LOCATION
(Might want to fix that, so as to make answering these type of Questions easier)

WHERE you live can make a difference
What does the Building Code, City Bylaws say / require ?

That’s where you need to start

Doesn’t matter what else you read ... in a book, or online
Or see on a YouTube
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
I am in Vaughan.

I know I will need a building permit and variance permit to build the addition. You mean local by law also determines if I can build from basement level ?
PointsHubby wrote: Your RFD Profile under your User Name is missing your LOCATION
(Might want to fix that, so as to make answering these type of Questions easier)

WHERE you live can make a difference
What does the Building Code, City Bylaws say / require ?

That’s where you need to start

Doesn’t matter what else you read ... in a book, or online
Or see on a YouTube
Deal Expert
Feb 7, 2017
15498 posts
12708 upvotes
Eastern Ontario
rdx wrote: I am in Vaughan.

I know I will need a building permit and variance permit to build the addition. You mean local by law also determines if I can build from basement level ?
Could

Yes, Bylaws can be Zone specific, relating to the local building code
So not just the Ontario Code
So a basement could either be a no go (slab only)
Or it could be the opposite, MUST have basement

Ya gotta start @ city hall to find out what you can and cannot build / do on your property
Deal Addict
Feb 22, 2007
1962 posts
225 upvotes
Mississauga
this is one of those things...you can't go back and fix...

you need to suck it up and make the basement portion as well...it will cost more, but the extra space will be beneficial and it will increase your house value.
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
I know, that's what I am thinking too. If $20k more, I would seriously consider that. However, some contractors are saying it could be $50k+ more.
pardnme wrote: this is one of those things...you can't go back and fix...

you need to suck it up and make the basement portion as well...it will cost more, but the extra space will be beneficial and it will increase your house value.
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
When I checked with city hall awhile ago about adding a sunroom on my lot, they checked and only mentioned that I need a drawing to apply the variance permit for changing the setback clearance. They also told me about the height limit of the addition, building permit and grading permit (if it is over 40 sq meter). I didn't ask about basement level up and they didn't mention that either.
PointsHubby wrote: Could

Yes, Bylaws can be Zone specific, relating to the local building code
So not just the Ontario Code
So a basement could either be a no go (slab only)
Or it could be the opposite, MUST have basement

Ya gotta start @ city hall to find out what you can and cannot build / do on your property
Deal Addict
Nov 16, 2011
1289 posts
979 upvotes
HAMILTON
I would get several estimates as I think you are dealing with a contractor who just doesn't want to do it for some odd reason.

There will be windows in it so it will certainly not be just another dark room...... jeez...... what a nonsense statement to make about dark room.

Makes sense to do a full height basement. I would also do a walk out to the rear or the side. Will almost double the living area
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
I found this video on YouTube, this guy built the ground level addition with concrete pier foundation, just by himself (of course I know he is not ordinary DIY guy, he obviously has all the trade skills). I wonder why contractors can quote $50-$100k for this job. It is mainly just concrete and wood, and of course lot of labor ;) I guess the contractor's profit and expensive labor would be majority of the cost........ Some contractors said just architectural drawing and permit cost $10k (I know various permits might cost at most $2-3K). The city actually doesn't need any professional drawing, they told me I could even just sketch myself on a piece of paper.

Deal Guru
User avatar
Oct 6, 2010
14433 posts
8823 upvotes
Toronto
IF I WERE YOU:

Look at my survey, see what the city by-law allows for a percentage to build.

You could benefit from the addition being built as a connection to the basement. ICF blocks sitting on footings for the support to which can be opened to the basement.

To build something like that, you are probably in the area of about $80k-$100k with permits/drawings and a vinyl siding finish etc...
DYI difficulty scale:
0-joke
10-no joke

¯\_(ツ)_/¯
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
Thanks for sharing your information.

I have the survey (site plan) of my house, how I can tell the % allowed from it ? You mean total square footage allowed (two levels) ? or % of the lot size ?

By the way, if I build from basement level, I would go with brick as my whole house is built with brick. The only reason I might choose stucco is if I go with one level addition and go with concrete piers foundation which does not support brick finish.

In terms of drawing and permit, I believe the total of variance permit, building permit, and ESA permit should cost no more than $3K. In terms of drawing, I was talking to an architect firm that was referred by a contractor I talked to, they were charging me $2k for drawing. I don't understand why I saw some quotes that state drawing and permit cost $10K.
koffey wrote: IF I WERE YOU:

Look at my survey, see what the city by-law allows for a percentage to build.

You could benefit from the addition being built as a connection to the basement. ICF blocks sitting on footings for the support to which can be opened to the basement.

To build something like that, you are probably in the area of about $80k-$100k with permits/drawings and a vinyl siding finish etc...
Deal Fanatic
Dec 5, 2009
5658 posts
3413 upvotes
I would dig out the basement. But it’s your money.
Deal Guru
User avatar
Oct 6, 2010
14433 posts
8823 upvotes
Toronto
You need to review your city by-law for building structures, this will tell you the percentage of land that can be used for structures, garages, etc... You may have to call the city's building department if you can't find out.

Some firms will charge you $2500 just for plans without any stamps, some outsource some work while others do them all in house. I was shocked when I was starting a project and was looking around for places to just do existing drawings and some of the prices were out of this world. I was quoted by a company at the home show in Mississauga, $5000 for pdf, 3 changes and 3d walk through.

If you can't get an excavator back there to dig this out, it's going to be substantially more expensive.

I recall correctly, a LxWxD trench of 15ftx4ftx10ft was about $12k by 2-3 people. Toronto of course.
rdx wrote: Thanks for sharing your information.

I have the survey (site plan) of my house, how I can tell the % allowed from it ? You mean total square footage allowed (two levels) ? or % of the lot size ?

By the way, if I build from basement level, I would go with brick as my whole house is built with brick. The only reason I might choose stucco is if I go with one level addition and go with concrete piers foundation which does not support brick finish.

In terms of drawing and permit, I believe the total of variance permit, building permit, and ESA permit should cost no more than $3K. In terms of drawing, I was talking to an architect firm that was referred by a contractor I talked to, they were charging me $2k for drawing. I don't understand why I saw some quotes that state drawing and permit cost $10K.
fdl wrote: I would dig out the basement. But it’s your money.

Agreed, this would probably be cheaper, lol.
DYI difficulty scale:
0-joke
10-no joke

¯\_(ツ)_/¯
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
Thanks for the information.

Good point about the access to backyard. Currently, the only access to the backyard is the single entrance door from the fence. When I did the interlocking stones in the backyard, the small Bulldog excavator was able to go in for the dig. Not sure how big excavator they will need to dig up the entire basement level of soil though. Also, it will be challenging to have the concrete mixer close enough to dump the concrete there for foundation. One contractor was saying he could use concrete blocks instead and it is cheaper as well.
koffey wrote: You need to review your city by-law for building structures, this will tell you the percentage of land that can be used for structures, garages, etc... You may have to call the city's building department if you can't find out.

Some firms will charge you $2500 just for plans without any stamps, some outsource some work while others do them all in house. I was shocked when I was starting a project and was looking around for places to just do existing drawings and some of the prices were out of this world. I was quoted by a company at the home show in Mississauga, $5000 for pdf, 3 changes and 3d walk through.

If you can't get an excavator back there to dig this out, it's going to be substantially more expensive.

I recall correctly, a LxWxD trench of 15ftx4ftx10ft was about $12k by 2-3 people. Toronto of course.






Agreed, this would probably be cheaper, lol.
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
Other concerns I have for digging down to the basement level would be:

* If the existing HVAC is big enough to support additional two levels of roughly 500 sq ft space. If not, additional cost for new HVAC system. By the way, I wonder how do contractors normally connect the existing HVAC to the addition? My basement is finished, does it mean they will have to open it up a bit to connect ? When I was getting quotes for sunroom, they all use standalone AC unit.
* Digging down to the basement level could have other wiring/piping underneath that might cost more $ and complications for the project.
* I didn't apply building permit but only ESA permit for finishing the basement. So, if I connect the new addition to the basement, inspector will see the finished basement during inspection.
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Oct 15, 2007
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rdx wrote: I found this video on YouTube, this guy built the ground level addition with concrete pier foundation, just by himself (of course I know he is not ordinary DIY guy, he obviously has all the trade skills). I wonder why contractors can quote $50-$100k for this job. It is mainly just concrete and wood, and of course lot of labor ;) I guess the contractor's profit and expensive labor would be majority of the cost........ Some contractors said just architectural drawing and permit cost $10k (I know various permits might cost at most $2-3K). The city actually doesn't need any professional drawing, they told me I could even just sketch myself on a piece of paper.

Do it yourself then. It’s just wood concrete and labour right? Seems like you have a lot of questions for someone who thinks that this work is so menial
Everything has been said before, but since nobody listens we have to keep going back and beginning all over again. - Andre Gide
[OP]
Deal Fanatic
Jun 7, 2005
8896 posts
687 upvotes
Red_Army wrote: Do it yourself then. It’s just wood concrete and labour right? Seems like you have a lot of questions for someone who thinks that this work is so menial
By no mean I think this would an easy DIY job for me. I am just saying if this experienced trade guy can do it by himself alone, I wonder why this job could cost $50K plus
Deal Fanatic
Jan 25, 2007
9676 posts
5060 upvotes
Paris
A windowless room in a basement has SO MANY uses... home theatre room, workshop, storage, sex dungeon... I would dig it out, at least for resale.
Deal Expert
Feb 7, 2017
15498 posts
12708 upvotes
Eastern Ontario
rdx wrote: By no mean I think this would an easy DIY job for me. I am just saying if this experienced trade guy can do it by himself alone, I wonder why this job could cost $50K plus
Cuz everyone is entitled to a wage equal to the resources they put into the job

Love how folks always think people in the trades have little skills to offer :rolleyes:

So WHY would they ever charge the rates / hourly fees they do ?

If it’s so damn easy ... do it yourself

You’ll quickly see that it is SKILLED LABOUR done by PROFESSIONALS that count the most in getting a job done right

Plus labour work, is hard work... literally back breaking.., tough on the body

May be not a big deal when you are 25, but a HUGE DEAL when you are 50

And these dudes are mostly self employed, so it’s not like a desk job with a multinational company

There is no cushy pension at the end of the road

Now consider yourself SCHOOLED by someone who grew up in a blue collar unionized household
Cuz your WHITE COLLAR prejudices are showing
And it’s not pretty
Deal Fanatic
User avatar
Oct 15, 2007
5154 posts
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PointsHubby wrote: Cuz everyone is entitled to a wage equal to the resources they put into the job

Love how folks always think people in the trades have little skills to offer :rolleyes:

So WHY would they ever charge the rates / hourly fees they do ?

If it’s so damn easy ... do it yourself

You’ll quickly see that it is SKILLED LABOUR done by PROFESSIONALS that count the most in getting a job done right

Plus labour work, is hard work... literally back breaking.., tough on the body

May be not a big deal when you are 25, but a HUGE DEAL when you are 50

And these dudes are mostly self employed, so it’s not like a desk job with a multinational company

There is no cushy pension at the end of the road

Now consider yourself SCHOOLED by someone who grew up in a blue collar unionized household
Cuz your WHITE COLLAR prejudices are showing
And it’s not pretty
Just another Perez Hilton
Everything has been said before, but since nobody listens we have to keep going back and beginning all over again. - Andre Gide

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