Planning an addition to house, need advice

[SkyHog]

My father and I are going to add another addition to the house (we did one about eight years ago), but this time we're facing a problem.

The place we want to add on to is on a heavy slope. What can be done to level it off? I took some pictures so y'all can see the connundrum:

dammit, wrong picture. stupid phone. one sec

 

[jesse]

dammit, wrong picture. stupid phone. one sec

should have bought an iphone...

 

[VtPilot]

dammit, wrong picture. stupid phone. one sec

lol

 

[ScottM]

should have bought an iphone...

Naw he can't, He works for T-Mobile which is the last to get anything cool or neat. They are also working to prevent other technologies from being adopted that would make them look even further behind. But they are a very good GSM provider. It is just that GSM is almost 15 years old now.

 

[SkyHog]

Naw he can't, He works for T-Mobile which is the last to get anything cool or neat. They are also working to prevent other technologies from being adopted that would make them look even further behind. But they are a very good GSM provider. It is just that GSM is almost 15 years old now.

Ummm...ok, yeah. So, about the add on?

(discussion about T-Mobile in other thread).

located here http://www.pilotsofamerica.com/forum/showthread.php?p=226000#post226000

 

[Teller1900]

The place we want to add on to is on a heavy slope. What can be done to level it off? I took some pictures so y'all can see the connundrum:

Kiddie pool...hose...30 bags of quick-crete.


Or a ****-load more river rock.

That's my idea.

 

[Richard]

A bedroom, a bathroom, a storage room, an illegal alien bunkhouse? What is it's intended use? Form follows function.

You gonna run water and elec out there? Does it need to match the roofline? Slab on grade, raised foundation?

If you wanted to do it on the cheap I would do minimal site work to prepare for raised foundation. The gable end of the house would be easy enough to match the roof pitch.

As far as going really cheap, ie, w/o permits, find out the schedule for the city bldg inspector...when he'll be in your area. Avoid material deleiveries for that time! Night deliveries are too suspicous so avoid that as well.

BTW: that is NOT a heavy slope.

 

[SkyHog]

A bedroom, a bathroom, a storage room, an illegal alien bunkhouse? What is it's intended use? Form follows function.

You gonna run water and elec out there? Does it need to match the roofline? Slab on grade, raised foundation?

If you wanted to do it on the cheap I would do minimal site work to prepare for raised foundation. The gable end of the house would be easy enough to match the roof pitch.

As far as going really cheap, ie, w/o permits, find out the schedule for the city bldg inspector...when he'll be in your area. Avoid material deleiveries for that time! Night deliveries are too suspicous so avoid that as well.

Thanks, Richard, but we're doing it legit. Its going to be an office, with power and probably heat/air vents. No water. We need to drop a slab (hence the issue with the slope), and we have not yet decided whether to match the roof or make it a flat roof below it.

We are very handy when it comes to building stuff, so we're doing it ourselves (minus the slab, because we both suck at concrete). The important part to start with is how to prep the area for the slab. I know it has to be flat, but the problem is that if we raise the left end (in the pictures) up, then won't it be really weak near the edge? If we dig the right side down, won't it weaken the existing portion of the house?

BTW: that is NOT a heavy slope.

Well, not too bad, but if you zoom in on the 3rd pic, you can see its about 1 foot over 10 feet of area.

 

[Greg Bockelman]

Well, it took several looks to figure out that you/someone was hiding in the bushes with the level. LOL

Do you intend to go all the way to the retaining wall that is there? Will the floor be a slab? Concrete?

The two options I can think of is to build a stud wall on that retaining wall, provided it will take the load, to the level of the floor and build up from there, or to pour or lay a concrete block wall up to the floor level and backfill it with dirt, and pour your slab on that.

That is the best I can do with the information at hand.

 

[SkyHog]

Well, it took several looks to figure out that you/someone was hiding in the bushes with the level. LOL

Do you intend to go all the way to the retaining wall that is there? Will the floor be a slab? Concrete?

The two options I can think of is to build a stud wall on that retaining wall, provided it will take the load, to the level of the floor and build up from there, or to pour or lay a concrete block wall up to the floor level and backfill it with dirt, and pour your slab on that.

That is the best I can do with the information at hand.

Thanks. That's my dad in the bushes, and I didn't even realise I got him in the picture. lol.

The wall in the back of the picture is going to come down, and the extension is going to go all the way to the back of the house. To the left, there is another cinderblock wall (its the sign that you're in Albuquerque), but its only a few layers high, and definitely not high enough to support anything for the house.

So - you think it might be prudent to lay the concrete at an angle (upside downish), so that it makes a flat top surface? That's not a bad idea, really. Backfilling may be a problem with the lower wall like that, but we can build that up a bit. Thanks!

 

[Greg Bockelman]

and we have not yet decided whether to match the roof or make it a flat roof below it.

Match the roof. In the long run it will look better.

I know it has to be flat, but the problem is that if we raise the left end (in the pictures) up, then won't it be really weak near the edge?

Not sure what you are saying. If you mean to just fill in with dirt, yes it would be weak. You need a retaining wall. A foundation wall in other words.

If we dig the right side down, won't it weaken the existing portion of the house?

In a word, no, because the wall is holding the dirt back now. Dig it down and the wall no longer needs to hold it back. But then you have a grade that does not match the floor level of the existing house. Unless of course the house has a basement.

The way I see it, you need to pour a foundation and back fill it to the existing floor level.

Well, not too bad, but if you zoom in on the 3rd pic, you can see its about 1 foot over 10 feet of area.[/QUOTE]

 

[Richard]

The issue then is how much can the existing retaining wall support? You want to be sure the soils are compacted (doubtful, but you never know) and if it aint just all sand backfill. You'll have a footing at the perimeter of the slab so you'll be digging anyway.

Is the house slab on grade foundation? (more than likely it is, very few raised foundations in the southwest desert) If so, there is an existing footing where you'd be digging down. So, no, you won't weaken the existing structure unless you plan on a Big Dig under the foundation.

Caveat, if you find you have to do some soil compaction, be careful to not damage the retaining wall. If you do you will have issues with your neighbor. You probably will anyway but don't give him something to chew into you.

How much will you pay for me to come place your slab? Cost plus.

 

[Greg Bockelman]

So - you think it might be prudent to lay the concrete at an angle (upside downish), so that it makes a flat top surface?

I am not sure what you mean by that.

If that wall to the left in the picture is only a couple of courses high, I would suggest taking it out and replacing it with a wall that goes up to your planned floor level. On three sides. Then you would have to fill it with dirt or gravel or something because you do NOT want to pour that much concrete.

That wall would have to be strong enough to hold the backfill plus the weight of the addition.

 

[Richard]

Greg, I think Nick means a slab with the profile of an isoceles triangle where the top of the slap is flat (hopefull level too) and the bottom follws the existing grade. This would result in the slab being thicker at the retaining wall.


For various reasons it is not a good idea to do this.

 

[wsuffa]

New concrete retaining wall, properly dug and anchored. Backfill above. Slab on top.

Nick, use a structural engineer that's experienced in your city. Yes, it will cost a little money, but it will be well worth it in terms of getting city approval and having a house that won't settle or slip.

 

[Richard]

another cinderblock wall (its the sign that you're in Albuquerque)

I thought the construction safety cone was.

 

[Andy Greever]

New concrete retaining wall, properly dug and anchored. Backfill above. Slab on top.

Nick, use a structural engineer that's experienced in your city. Yes, it will cost a little money, but it will be well worth it in terms of getting city approval and having a house that won't settle or slip.

Best advice you've been given so far.



Don't skimp on the foundation.

Match the existing roofline.

Remember to put the plumbing where you need it before you pour, unless you plan to pipe through the attic.

You'll still save mucho bucks doing everything else yourselves.

Have fun!

 

[TMetzinger]

Even if you don't think you want plumbing now, put in the necessary infrastructure (hot and cold supply and a drain tube) and cap them off. A lot cheaper to run new plumbing from the stubs in an addition than it is to have to run new plumbing INTO the addition later on.

Same thing with electricity. I'd suggest the addition gets it's own subpanel, with a high-current tie from the main panel.

 

[SCCutler]

I have no idea why Bill Suffa knows this stuff, but he said what I was going to say. There sure are a lot of smart folks here.

Most importantly, I also would urge that you consult an engineer for the foundation- won't cost much, and I'll betcha the city will want to see an engineer's seal on the foundation plan anyway.

 

[Capt Binkley]

Completely layman's opinion (my wife is the architect, not me) but I'd assume you're going to need to beef up that retaining wall on the left. Possibly take it out and replace it with higher and wider. Then backfill the area and level it off.

Might seem like a simple problem, but I'd really recommend you contact a professional in your area. Building on back fill is not to be done lightly. You don't want to walk into that room 3 years from now and find a crack in your ceiling from wall to wall.

 

[Lawreston]

BTW: that is NOT a heavy slope.

I guess this is indicative of a heavy slope. The ends and upper foundations are poured into the space blasted out of tons of ledge.
Photos are prior to purchase. Leaves, pine needles, suckers and other junk trees have since been raked, sawed, and cleared from most of the 1.6 acres. Who said retirement accords a lot of free time and relaxation?

Good luck on your project, Nick; a lot of good advice has been posted.

HR

EDIT: Winter shall prove to be interesting. The last photo is from 1/2 way down the hill from my driveway.

 

[Richard]

Harley, that's a nice property. 20% grade is usually the cutoff for a good amount of slope. 30% is the limit for a build site.

 

[tonycondon]

Harley,

my parents driveway is similar, maybe a little steeper. the trees are closer on the sides though. it makes for a good reason to not have to go anywhere when it snows like hell. heat up some hot chocolate and enjoy the view out the window.

 

[Teller1900]

Harley,

my parents driveway is similar, maybe a little steeper. the trees are closer on the sides though. it makes for a good reason to not have to go anywhere when it snows like hell. heat up some hot chocolate and enjoy the view out the window.

Tony, your parent's driveway is like suicide. It's loose washboard rock that my car had issues clearing when it was sunny and dry

 

[tonycondon]

lol matt, you shoulda seen Jesse when he drove down it on his motorcycle at night. He was kind of shaking when he made it to the bottom. He just drove up the yard to get out, didnt even try the actual driveway.

 

[Lawreston]

Harley,

my parents driveway is similar, maybe a little steeper. the trees are closer on the sides though. it makes for a good reason to not have to go anywhere when it snows like hell. heat up some hot chocolate and enjoy the view out the window.

When I was "considering", a bakery shop owner near the bottom of the access road -- and who lives nearby -- told me, "It can be a trial on the worst of winter days." My immediate thought was, "On the worst of winter days as long as there's sufficient kitty food on the shelves, propane gas for the Empire back-up heat, beer in the fridge and food in the pantry, who cares? I no longer have to be somewhere daily at an appointed morning hour.

HR

 

[etsisk]

nah, not such a heavy slope - you can do a raised foundation, or you can do a walled slab sort of thing (heh - not up on construction terms of art, I fear).

At any rate, it's doable.

 

[Lawreston]

The house was built in 1997, the garage in 2000; a 2nd home for a guy who was/is on the road 40 weeks of the year, hence the most unlived-in house in Georgetown. I closed on June 01, moved in on the 7th; and uncountable pick-up truck loads of grounds clearance(including fallen dead branches and additional prunings) have gone to an acquaintance's nearby stump dump.

HR

 

[JohnR]

Skyhog, hire an architect.

 

[SkyHog]

Skyhog, hire an architect.

Heh - that is probably the prudent thing to do, but my father and I have build other additions to the house (including getting permits and inspections done), so we're good at that stuff.

Plus - I really enjoy doing this kind of stuff. Not to get too morbid, but it may be one of the last major projects my father and I get to do together (nothing's wrong except time).

I give you this though, every time we do something like this, we make a deal before hand, that if the project gets to the point where we can do nothing right anymore, we stop, cut the loses and have a pro come do it.

 

[Pjsmith]

The slope doesn't look that great. You're going to need some lateral support anyway, so I'd look into (or look into hiring an architect who would look into) doing this as a shallow spread footing for the three perimeters and pouring a short foundation wall that ties into the perimeter footing of the existing slab.

EDIT: Is that another house to the left? How much do you have before you hit the building setback line?

 

[SkyHog]

The slope doesn't look that great. You're going to need some lateral support anyway, so I'd look into (or look into hiring an architect who would look into) doing this as a shallow spread footing for the three perimeters and pouring a short foundation wall that ties into the perimeter footing of the existing slab.

EDIT: Is that another house to the left? How much do you have before you hit the building setback line?

I'd say there's about 50 feet between the houses (and yes, that is another house). The end of our property is the wall.

 

[SCCutler]

I'd say there's about 50 feet between the houses (and yes, that is another house). The end of our property is the wall.

Nick, something is not computing here. If that is the next house over on the left in the photos, then there ain't no 50' 'twixt yours and theirs. In any event, if the retaining wall on the left is your property line, be VERY careful to make sure that you have the right to build up to it (or how closely you can build to it).

Assuming a routine setback requirement (rarely seen less than 6' in non-zero-lot-line plats), you don't have room for much of a room there.

Caveat Builder.

 

[JohnR]

Heh - that is probably the prudent thing to do, but my father and I have build other additions to the house (including getting permits and inspections done), so we're good at that stuff.

Plus - I really enjoy doing this kind of stuff. Not to get too morbid, but it may be one of the last major projects my father and I get to do together (nothing's wrong except time).

I give you this though, every time we do something like this, we make a deal before hand, that if the project gets to the point where we can do nothing right anymore, we stop, cut the loses and have a pro come do it.

I watched Top Gun and can fly a Cessna, so I should be good at being a fighter pilot, eh? Seriously, there's a reason the professions of Architecture and Construction require government licenses. Just be careful, ok?

Consider the resale value when the realtor tells the potential buyer the addition was done by amateur contractors, plus the insurance implications.

 

[Richard]

if the project gets to the point where we can do nothing right anymore, we stop, cut the loses and have a pro come do it.

When I was in the business I loved guys like you. Real cash cows. You're stuck twixt and tween. 5 x shop rate.

I knew on the first phone call, nay, the first word on the first phone call. "Haaaaaaaalp!"

And Spike nailed it; the word of the day is setback. As in, what is the set back, as measured by the nearest portion of the structure, from the property line? That's any point on the structure, including the facia boards.

And there are certain requirements which determine if you need to pull permits, schedule inspections and so on. You do NOT want to get to the end to find out you need to remove a portion of the structure because you skipped a phase inspection. You could get an As Built permit but that can be expensive. It's only money anyway. Let the fun begin!

 

[JohnR]

When I was in the business I loved guys like you. Real cash cows. You're stuck twixt and tween. 5 x shop rate.

I knew on the first phone call, nay, the first word on the first phone call. "Haaaaaaaalp!"

And Spike nailed it; the word of the day is setback. As in, what is the set back, as measured by the nearest portion of the structure, from the property line? That's any point on the structure, including the facia boards.

And there are certain requirements which determine if you need to pull permits, schedule inspections and so on. You do NOT want to get to the end to find out you need to remove a portion of the structure because you skipped a phase inspection. You could get an As Built permit but that can be expensive. It's only money anyway. Let the fun begin!

Exactly.

As an architect, I don't even take jobs where the owner got caught with his pants down (working without a permit). I used to, but it made me squeamish and no amount of fee ever made it feel any better.

 

[Lawreston]

And Spike nailed it; the word of the day is setback. As in, what is the set back, as measured by the nearest portion of the structure, from the property line? That's any point on the structure, including the facia boards.

A big time developer here in Maine(formerly, till he left several large projects in the lurch and skedaddled to Florida), in one of his developments built a house which sold and was occupied for quite a long time. Eventually, the owner decided to sell the house; nothing unusual. When the buyer's title search was done there was a slight problem. The structure was eight feet over the line of the adjoining property. There became lengthy and costly litigation while the buyer's bank held the deal in abeyance.

HR
((Side note to JohnR: Same developer became chastised by the State of Florida for certain matters re developments there.))