Cabin Placement on Slope.

[HoustonDave]

Wife and I are in the process of designing our cabin based on the Builders Cottage.  For now, we are using a 16'x16' footprint to get a feel for scale and placement.  I'm interested in yall's thoughts on the three locations.  

We can get within a couple of feet of the water.  We will probably have to put in an aerobic septic system.  The lot is about 200' from road to water and about 120' wide.  We are leaning toward a 16x24 version of the Builders Cottage with loft, adding on wings down the road to expand sleeping areas.

The next two images are screenshots from a rough Sketchup mockup that show the land contours and three potential cabin placements.  (Just started using Sketchup, man it is nice...)





The land is already cleared of underbrush and has some large trees.  All three potential cabin locations would have generally unobstructed view of the water.  The highest might need some limbs thinned out.  Elevation change from water to top level shelf is about 50' up over 200', but as you can see it gets pretty steep at the shelf edge.  Don't have soil specs yet.

Here are some pictures from the top of the slope looking toward the water



View from the shelf at the top looking toward the lake.  The shelf stretches about 60' out from the road and runs most of the width of the lot.



View looking downslope from the next lot over.  It has a smaller shelf and more gradual slope.



View looking at the lot we are buying from the lot next door.  You can make out the shelf in the left portion of the picture and see how it drops off toward the water.

Electricity and water are available at the road.

[glenn kangiser]

I don't like people seeing what I'm doing and don't care much for other peoples noise...mine is fine though.

Guess I'd choose the middle if there were boats on the lake and cars on the road, unless it impacted my use of a leach field if that is needed with your septic system.  With the aerobic system you may already be pumping.

[HoustonDave]

Boat traffic is pretty low.  No jet skis or ski boats allowed.  Smaller lake, so no need to get in a hurry.  And the road is a dead-end one laner, so not like you'll see a ton of traffic.

[glenn kangiser]

Sounding better all the time.

[bayview]

   You might be surprised at how much utilities will cost installed.   A longer run will be cost more.   Also,  closer to the road for the driveway will be less expensive.

   I would try to find the best view of the lake that would be closest to the road.   Look for where the water naturally runs off.   Obviously, you wouldn't want to build where there is potential flooding due to runoff.

   You will also want to locate the home for further expansion. . .    Outbuildings, off street parking etc. . . .

   Does the lake get "stagnant" during long periods without rain?   Our lake at Whitney does when we have our annual "algae bloom".   You wouldn't want to be right on the water for that!

   Placement for the septic tank would be a consideration.

   Is there a "natural" clearing that you can take advantage of . . .    Without to much clearing of the land.   Leveling the lot, cutting down trees and removing stumps can get pricey.

   Is the soil more sandy in some areas, more rocky in others?   Might be a consideration for the foundation.   I wouldn't think you would pour a "pad" of such a sloping lot. . .

   What have the neighbors done for placement of their homes?   You might want to find out why they placed their homes where they did. . .    Besides, they will love being part of your building process!   A happy neighbor will more easily put up with construction noise and mess.   

   I removed a dead tree for a neighbor, and graded a yard for another neighbor when we started our construction.   Smiles and waves whenever we see them.   And, "just let us know if you need a hand".

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[bgarrett]

I like the middle position

[Barry Broome]

If this is going to be a weekend/getaway cabin that you'll only be in once in a while... then I'd place the cabin nearest the water.

If you're going to be living there then I'd go middle or nearest the road.

My thoughts are that if you only visit once in while then a bad driveway (which may an issue based on lack of investment and water erosion on hill) won't be as big a nuisance.

However, if you're going to live there then the convenience of being closer to the road might be worth less hassle.

I also don't like the idea of someone being able to stare at my house from the lake... if I'm living there all the time. Again, if it's only for a weekend here or there I wouldn't care and being close to the lake would be more important.

[HoustonDave]

Thanks Bayview

You might be surprised at how much utilities will cost installed.   A longer run will be cost more.   Also,  closer to the road for the driveway will be less expensive.

Supposedly, the electric company will run electricity to a pole, meter, and panel for free from the road.  I haven't gotten specifics.  The water is a private well system owned by the community.  I'd assume I can run the pipe for that myself.  You have a good point on the driveway.  I think we'd use part of the shelf for parking regardless of whether it meant walking downhill a bit to the cabin.  We'd probably have to rethink that if we keep the property into our retirement years.

I would try to find the best view of the lake that would be closest to the road.   Look for where the water naturally runs off.   Obviously, you wouldn't want to build where there is potential flooding due to runoff.

Gotcha.  There is a small gully that runs down the right side of the slope as you are facing the lake.

You will also want to locate the home for further expansion. . .    Outbuildings, off street parking etc. . . .

Right.

Does the lake get "stagnant" during long periods without rain?   Our lake at Whitney does when we have our annual "algae bloom".   You wouldn't want to be right on the water for that!

They pull the water from the bottom of the lake and it is spring-fed.  Even with the dry spell we've had this year (very low rain and Toledo Bend Lake for example is 10' below full pool) the lake level is only about 6" down and there is good water flow in and out.  They tell me they don't get stagnation problems.

Placement for the septic tank would be a consideration.

Yep.  Will be an aerobic system, so it will be pumped.  Does that mean we can put it pretty much anywhere?

Is there a "natural" clearing that you can take advantage of . . .    Without to much clearing of the land.   Leveling the lot, cutting down trees and removing stumps can get pricey.

There are good clear spots up and down the slope.

Is the soil more sandy in some areas, more rocky in others?   Might be a consideration for the foundation.   I wouldn't think you would pour a "pad" of such a sloping lot. . .

It looks pretty uniform.  Mostly sandy maybe some clay with small sandstone chunks throughout.  I'll need to get the soil spec'd out.  I was planning on pier / post / beam construction.  Is it required to level the lot if I'm doing that?  I want to disturb the soil as little as possible.  Can you build on a slope by setting the piers and leveling using varying post height without actually leveling the soil under the footprint of the cabin?

What have the neighbors done for placement of their homes?   You might want to find out why they placed their homes where they did. . .    Besides, they will love being part of your building process!   A happy neighbor will more easily put up with construction noise and mess.

I've seen some variation.  Most tend to build near the top at the road or right at the edge of the upper slope, but a couple have built closer to the water.  I'll try to find some photos and will be sure and ask around.  Thanks for the advise.  Much appreciated.

[HoustonDave]

If this is going to be a weekend/getaway cabin that you'll only be in once in a while... then I'd place the cabin nearest the water.

If you're going to be living there then I'd go middle or nearest the road.

My thoughts are that if you only visit once in while then a bad driveway (which may an issue based on lack of investment and water erosion on hill) won't be as big a nuisance.

However, if you're going to live there then the convenience of being closer to the road might be worth less hassle.

I also don't like the idea of someone being able to stare at my house from the lake... if I'm living there all the time. Again, if it's only for a weekend here or there I wouldn't care and being close to the lake would be more important.

Thanks Weasel.  Since we have "city cars", we'll probably park at the top.  It would be expensive to put in any driveway I would trust those weenie cars to drive up and down.   

That means wherever we put the cabin, we'll have to walk from the top.  Maximum walk of 150' depending on cabin placement.  Right now it will probably not be full time, but it may come down to whether we end up retiring there in 20-25 years.  Another thing to consider is that this is a private gated lake with 75 owners, so it's not like some stranger will be boating up and eyeballing your property.

[bayview]

HoustonDave:

  As for the septic. . .    The installers will need access to place the tank, run the sewage pipe, the electric and locate where the effluent will be dispersed.   They will also need to service the tank.   Which may include an occasional "pump-out".   It might be a good idea to contact the installer before deciding on where to place your home.  

   You might be a good candidate for a composting toilet with a gray water system.   Other forum members have gone this route and would be of great help. . .

  For soil conditions . . .   Again, this is where the neighbors will be helpful.   What have they done?    In lighter soil and on a slope you may want to consider a post-pier foundation with a solid concrete wall on the uphill side.  

   

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[MountainDon]

I'd go middle to top. I would not go right at the lake side as what guarantee have you thet the water level will not rise? Of course it could also go down too



Back home friends family had a cabin on a small lake for decades. That lake level was stable for decades and then something changed. I don't know what or if it was ever figured out. The water lever went up a few feet at that lake and a few others in the area. And it has stayed that way.

[HoustonDave]

Thanks Bay and Don.

Looking at joist spans, I see the Builders Cottage has beams set so there are two beams for the 14' span.  That's each beam set 2' 2" from the edge, so there is 9' 8" between the beams to cover the 14' span.  It calls for 2x6 joists.

I have seen joist and beam tables showing that (assuming 2x6 floor joists on 16" centers) you can span 9'10" between beams.  So that design makes sense.  You have a middle section of 9'8" between the beams, and a little over 2' cantilevered at each end.

Seems if I want to increase the floor to 16' wide, I have three choices:

A) Cantilever another foot on each side.  So 3' 2" is hanging over.  Based on what I've read this is a baaddd idea.  To quote one page:

As a general rule, good construction practice would indicate that the maximum extension for the cantilever should be no more than twice the depth of the joist lumber, as shown in Figure 5. As an example; an 8 inch joist should have a maximum cantilever of 8 inches and a 10 inch joist should have a maximum cantilever of 10 inches.. Following this rule will basically eliminate all vibration and deformation caused by the cantilever.

Also:

If the cantilevered joist runs in the same direction as the structural floor joists, the tail portion of the joist should extend inward within the floor joist framing a minimum of 6 times the length of the cantilever portion of the joist.

A length of 6 times the cantilever will help to prevent any deformation or movement of the tail joists if they are subjected to a heavy live loads, as shown in Figure 6.

http://www.renovation-headquarters.com/cantilevers-2.html

So basically, for a 14' 2x6 joist the maximum cantilever is about 2' (because 14' - 2' = 12' (the tail) and 12' * 1/6 = 2' (maximum cantilever).  But the 'better safe than sorry' amount is that if you are using 2x6 joists, you don't want to cantilever more than 6"...right?

B) Increase floor joist size to 2x8 on 16" centers.  This would give me a maximum center span of 12' 4" between beams.  I could keep the two beams and the approximately 2' cantilever.

C) Keep 2x6 joists, move the two beams to the rim / perimeter, and add a third beam in the middle.  This would give me about 5.3 foot spacing between beams. 

I looked at going with 12" joist centers and keeping the original beam and 2x6 joist configuration, but that doesn't quite give me the span I need.  Max span is only 10' 10" between beams for that, and for a 2' cantilever I'd still end up with a 12' span between beams.

I'm tempted to go with option B here.  The reason being that having a third beam means an additional row of piers and posts.  If I get settling down the road, I've heard it's a lot easier to re-level a foundation based on two beams than it is three beams.  Right?  Is there a reason to NOT go with the 2x8 joists?

Anything I'm missing here?

[MountainDon]

Or, for a 16 foot width...
(D)  Place a beam directly under each long wall (no center beam; who wants to dig all those holes anyhow    )
Then use 2x10 or 2x12's for floor joists. Depending on species and grade, 16" centers...
   2x10 SYP #2 spans up to 16'1"
   2x10 Hem-Fir #2 spans up to 15'2"
   2x10 DF #2 spans up to 15'7"
and remember that the span distance is measured at the inside of each beam, not at the outside edge.
The above are near the maximum, not always a good idea to push to the limits, so maybe 2x12 would be better?  


Or (E) Place the beams within 10-12 inches of the outside wall line (more or less what I did) and use 2x10 joists on 16" centers.

(someplace on the site John pointed out that the 14 foot wide and narrower plans with generous cantilevers should not be taken as a starting point to scale up to greater widths. Choice (A) is a bad idea as you noted. IMO, choice B is not a good idea for 16 feet wide either.)

[stricsm]

We have a weekend lake/river cabin on a very similar slope as yours.  Our cabin is located in approximately your middle position.  We bought the property five years ago with the cabin in place and are very very slowly fixing things inside and out (we added a modified version of John's sunroom on the back facing the water with a deck attached).  Anyway, our view from the top of our property is great in the winter but not so great in the summer due to trees/foilage.  The middle position view is good year round but not great.  Wherever you put it, make sure you have good drainage around your foundation.  We have a hybrid foundation (part traditional & part post and pier).  My next big job is to install french drains on the upslope side.

BTW, I like our cabin being closer to the water on a slope.  It feels like a treehouse and we spend most of our time in the sunroom facing the river enjoying the view and destressing.  It feels good close to the water.  I don't think it would have the same feel at the top of the hill.

Good luck - your property is beautiful. 

[HoustonDave]

Don,  I'll lean toward:

Or (E) Place the beams within 10-12 inches of the outside wall line (more or less what I did) and use 2x10 joists on 16" centers.

Might even go with 2x12 here, since I'm planning on a 1.5 story with a 4' wall on the half story.  When in doubt, spend a few extra bucks and over-engineer, eh? 

[HoustonDave]

We have a weekend lake/river cabin on a very similar slope as yours.  Our cabin is located in approximately your middle position.  We bought the property five years ago with the cabin in place and are very very slowly fixing things inside and out (we added a modified version of John's sunroom on the back facing the water with a deck attached).  Anyway, our view from the top of our property is great in the winter but not so great in the summer due to trees/foilage.  The middle position view is good year round but not great.  Wherever you put it, make sure you have good drainage around your foundation.  We have a hybrid foundation (part traditional & part post and pier).  My next big job is to install french drains on the upslope side.

BTW, I like our cabin being closer to the water on a slope.  It feels like a treehouse and we spend most of our time in the sunroom facing the river enjoying the view and destressing.  It feels good close to the water.  I don't think it would have the same feel at the top of the hill.

Good luck - your property is beautiful.  

Thanks Stricsm, I appreciate the tips and insight on placement.  Good luck on fixing up your place!

[johnky]

no one has mentioned the flood plain yet so I'll throw that into the mix.  You can lookup FEMA flood maps for your lake.  Just google "flood plain maps" and you'll get to the FEMA maps.  You want to build above the level of any potential flood.

Another thing I'll throw in is that it's always better to pump potable water uphill and then let the gray and black water run downhill.  This rule of thumb may make all your decisions easier.

stricsm made a great point about winter vs. summer.   Have you been on your place in both seasons?  This may make your decision easier for you.  The change in lake views may be dramatically different.

You mentioned that you'll be walking up to 150' if you put the cabin low near the lake.  That sounds like a nightmare to me.  Are you really prepared to walk 150' through the mud and rain just to bring in your groceries on a rainy day?  Personally, I like being able to drive right up to my shop and cabin and load and unload stuff.  It sure makes life easier and saves a lot of time.

Good luck and congratulations on getting such a beautiful place!

[dridril]

what lake is your place on  and i agree on the 150' walk - would be a major pain

[HoustonDave]

johnky,

Did some checking and looks like the first 50' or so is in "Zone A".  That leaves about 150' upslope fully out of any FEMA flood zone.

Basically my understanding is that for Zone A, FEMA uses an approximation method to determine whether there is a 100 year (1% per year) flood risk.  No one actually visits the area and does an engineering analysis.

dridrill,

It's Lake Ioni, small private lake and hunting/fishing club.  Not closed on the property yet.

[johnky]

If you're not completely sure about the flood zone, you can do your own survey.  Look very carefully at the trees to see if you can discern a line across them - all at the same height.  The marks on the trees will last about 10 years.  Also look for any giant logs suspended way up on the banks.  This is more common on rivers that flash flood but sometimes you can see where floating debris jammed up in the forest near the shore to get a height of previous floods.  You can also look for any cabins that are near the shore and ask the owners when they built and if they ever saw a flood.  That might get you back 20 years of history or more if you're lucky.

You can also look at the topo maps to see if there is a natural spillover.  For instance, I've got some land in Florida on a lake that is surrounded by hills that rise about 75' above the normal lake level, except for one low hill.  The lake level will rise about 30' if there is a big storm or hurricane.  Once it floods 30' higher than normal it spills over that low hill and beyond that is a huge lowland area of several square miles of farmland.  Theoretically, it could never go above 30' because of that natural spillover.  Then again, there are always the stories like the campground in Arkansas last June where 18 people died.  That campground had been in that valley for a long long time and nobody expected a flood - they all thought the surrounding area could handle the overflow of runoff but it didn't.  It was just way too much water coming down too fast.  Even the cabins and RV's parked high on the banks were swept.

[johnky]

B) Increase floor joist size to 2x8 on 16" centers.  This would give me a maximum center span of 12' 4" between beams.  I could keep the two beams and the approximately 2' cantilever.

I'm tempted to go with option B here.  The reason being that having a third beam means an additional row of piers and posts.  If I get settling down the road, I've heard it's a lot easier to re-level a foundation based on two beams than it is three beams.  Right?  Is there a reason to NOT go with the 2x8 joists?

Anything I'm missing here?

You might want to check out John's 20x30 1-1/2 story cabin plans.  That set is similar to the builder's cottage but doesn't have a cantilever.  I know it's extra money to buy that plan since you already bought your builder's plan but it might be worth it. 

My problem was a bit opposite of yours,  I had the 20x30 plans already and then changed my mind and decided to downsize to 16' wide.  I decided, with John's help, to keep all the lumber dimensions the same as shown on the 20x30 plans and just shorten the width to 16'.  John might be able to explain the differences between the plans better than I am.

In the 20x30 plans, you have two girders that are site built from 2x12's.  You then run full length 2x12 floor joists across the entire 20' span (16' in my case).  This may sound a bit overbuilt, but the clincher for me was that I'm going to have a wraparound deck and using 2x6's for floor joists was too small to tie in to the porch joists so I decided to stick with the 20x30 plans and just change it to 16'x24'.   I also didn't want a center girder and the extra piers that are required for a center girder.

[HoustonDave]

Thanks John.  Good comments and I'll talk to John Raabe about getting the 20x30 plans.  Safer to take a plan for a larger space and downsize keeping dimensions than to try to scale up blind.

[HoustonDave]

You can also look at the topo maps to see if there is a natural spillover.  For instance, I've got some land in Florida on a lake that is surrounded by hills that rise about 75' above the normal lake level, except for one low hill.  The lake level will rise about 30' if there is a big storm or hurricane.  Once it floods 30' higher than normal it spills over that low hill and beyond that is a huge lowland area of several square miles of farmland.  Theoretically, it could never go above 30' because of that natural spillover.  Then again, there are always the stories like the campground in Arkansas last June where 18 people died.  That campground had been in that valley for a long long time and nobody expected a flood - they all thought the surrounding area could handle the overflow of runoff but it didn't.  It was just way too much water coming down too fast.  Even the cabins and RV's parked high on the banks were swept.

Thanks John.  The water level can't get too much higher because it would wash out the dam at the back end of the lake.  The lake has a bottom draw to keep oxygen turnover, and then it has an overflow spillway, and finally you have the dam height.  I don't think the water could get much higher than 5' above current level.  I'll definitely check the trees and ask the neighbors though.

[John Raabe]

Yes, narrowing a plan will just make the floors and roof more sturdy and lower the stress on the beams and piers.

Here is the link to the 20' wide 1-1/2 story: http://www.countryplans.com/20w_loft.html

You can also check the Plans Support forum postings for modifications and info on variations others have done or asked about.

[HoustonDave]

Ordered.  Thanks John.