Frost protetected slab detail work

This weekend work took me to the inside of my slab where I installed insulation and fill in preparation for the cement truck.

Work began with me attaching the outside foam to the forms to prevent them from moving around too much in the cement.  Screws or nails will simply pull thru the foam so I needed to improvise a way to securely attach the double foam sheets.  I used a nail and some fence wire to create a “T”.  Then I drilled a 1/8 inch hole thru the foam and forms.  After threading my “T” fastener thru the 1/8 hole I pulled the wire tight and wound it around a screw driven into the form.

The edges of my slab need to be 12 inches wide per IRC.  To meet the frost code I also need at least 16 inches buried below the ground and 8 inches above.  That makes my slab 24 inches thick which happens to be the dimension of the XPS foam I am using.

The center part of the slab will be 4.5 inches thick so that makes the “channels” on all four sides will be 19.5 inches tall.  I took a standard sheet of XPS foam and cut off 4.5 inches for the pieces used inside.

At one point I Was going to use 4 inches of foam for these inner pieces but after some napkin calculations I realized that the difference in heat loss was going to be 4% more with 2 inches versus 4 inches.  Frankly, that just was not worth the $140 to me.

I obtained a 16 foot long 2×6 that I will be using as a concrete screed and to help me set the inner forms at 4.5 inches.  Next I cut some 12 inch wood blocks to help me set the spacing between the outer and inner foam walls.  I also drove in some 3 foot long lengths of rebar to act as a brace for the inner insulation.  With all this in place I set the inner foam sheets and braced the bottoms by packing in gravel.

Next the hard work begain….filling the center.  I quickly learned that my little BX25 did not have the reach I thought it had.  I was barely able to get the fill over the inner form and I ended up moving an awful lot of dirt by hand.

Let me tell you a wheelbarrow of bank run gravel is so heavy that it’s almost too heavy to move.  After a lot of hours of sweating I finally had the center mostly full.  During the fill I had to install a lot more 12 inch braces to make sure that the foam would not collapse.

The center is very well compacted, but I stayed away from the edges to prevent them from bowing and/or collapsing.  I will do a pass around the edge with a small tamper to make the edges really solid.


I need to dig out some trenches for drain pipes and get the plumbers to stop by and do their thing.  View the gallery for all the weekend pics.

Big pile of dirt and other random thoughts

I was in need of quite a bit of fill for the middle “hump” of the slab and backfill for after the slab is poured.  I called up Graves Stone and Gravel and had a 20 yard truckload sent over to the lot

Last night I double checked the top of my slab forms to make sure they were still level.  I placed my water level on one corner and checked the top every 2 feet.  I would say that I am within 1/16 of an inch from level on the forms.  The next step is to attach the bracing to keep the walls from bowing inward or outward during the pour.  After that I will begin building up the hump in the center of the slab.

As part of the inner slab work I have an interesting thing that I am doing so that my well water tank will be below the floor so it won’t take up space in the house.  It involves building forms for a pocket in the middle of the slab….hope it works.

I have made the call that my concrete pour will be on Sept 8th in the morning.  I still have tons to do including inspections and finding a plumber.  I will have lots of pics on Monday…have a nice weekend!

Nokero N210C Product Review

I have a “thing” for solar-powered LED lights so today I will review the N210C made by Nokero.  This model is the same as the N200 except it comes with a digital camo pattern and a rubber bumper.

The idea is to produce solar lights to replace kerosene for lighting in third world countries.  Having used kerosene for space heating on several occasions, I can tell you that it is a pretty stink substance burned and unburned.  I imagine that the “stink” is probably not in any way good for the health of those in the vicinity.

Ordering and Delivery

Ordering was pretty easy on the Nokero website.  I paid using my Paypal account.  The delivery was not what I would call speedy as it was shipped from Hong Kong using the US postal service somehow.  It took about 20 calendar days to arrive at my doorstep.  Not what I would call speedy compared to say Amazon where stuff shows up two days later.  At any rate it arrived in a cardboard box that looked like it was packed by an 8 year old (who knows maybe it was).


The device is operated by sliding a tiny switch right or left to use either the high brightness or low brightness mode.  The switch is covered by a rubber boot that keeps the rain out.  Frankly the rubber boot is a pain in the ass and makes it tough to operate the switch.  Perhaps a taller switch would operate easier.

This model comes with a rubber bumper which I think is useless and would not recommend you spend money on.  The digital camo pattern is nice and matches the cover of my couch (most of the reason I bought this model over the N200).

A clip on the top of the device works well for hanging the device on a hook.  I now have tiny hooks installed all over my XS house so I can hang my light.  On high the brightness level is very good and on low it’s also pretty good.  I would say that the low setting works well for navigating around and general lighting.  The high setting probably is best for reading or other detail work.  Frankly, in a pinch either mode would be just fine for reading although I suspect that long hours might become tiresome on the low setting.

I used the light for a few hours on both high and low modes while I listened to the Patriots game and the brightness remained constant.  Out of the package I used three hours of battery and it was still going strong.  I have installed a tiny hook on the outside of my XS house so the N210 can charge during the day.

N210C Running on Full Power….Mmmm

I admit to being a bit critical in this review, however I really do like this light.  A few tweaks on the next generation and it will be really great.  Compared to the d.light I reviewed the N210/N200 is a much better value and a much better light in my opinion.  I do plan to order more, probably from someone on Amazon this time.  They do have an updated model with brighter LED’s (N220) maybe I will try one.

I will continue to use it and see how it operates over a longer period of time.  I will write a long-term review when I have spent enough time with it.  Right now, I give it a big thumbs up!

Completed Slab Forms

This weekend I completed the forms for the slab.  The forms are made from 2×6 lumber that I will recycle back into the house.  I will be pouring cement against the foam insulation so the lumber will not get very dirty.  The gallery at the bottom of this post has the pics from this weekend.

Form Base

I created the base of my forms by nailing a 2×4 to a 2×6 to create an “L” shaped footing.  Every 2 feet there is a place for an upright and a hole drilled for a 1/2 inch piece of rebar.  A 2 foot length of rebar is driven into the ground to help keep the bottom from moving.  The upright will be used to support the rest of the form.

Also notice that I have installed a nail in each corner to measure for squareness.  I used a clothes pin style clamp to hold one end.  I typically work alone and since my dog has not yet learned to hold one end of my tape I need to use the clamp.

After squaring the base to within 1/16″ I drove in my rebar stakes checking the squareness after each stake.

Form Uprights

I cut a bunch of 21 inch tall uprights out of 2×4 for upright members.  I sized these members short to keep them away from the top lip of the slab.  To get started I nailed these pieces in place on the footer board with an air nailer.

Top Rail

With the uprights in place I began attaching the critical top plate which will set the top of the slab.  This piece must be 100% level and straight or your slab will not come out good.

I use squeeze clamps to hold one end of each plank as I attach it.  I had the laser set up and I would line up each plank to hit a 1/2 inch mark I had made on each. As I went along I verified each plank with 4ft level and the water level.

I used 3 inch screws to attach the top plank so I can adjust it should I find something wrong.  At this point I believe that my top is within 1/4 inch of being correct, possibly better.


I installed corner and mid bracing on the outside of the slab although I have not yet nailed it down yet.

The first thing I do is install a 2ft 2×3 stake in a spot where there are no rocks.  I use a landscape bar to “drill” a pilot hole and then drive in the 2×3 stake.  I used the chop saw to make the ends of the stake pointed.

With the stakes in, I cut to fit a 2×3 piece to brace the bottom of the form.  Then I cut the diagonal pieces and lay them in place.  The diagonal piece has the corners chopped off to make them fit better.

The final step will be to nail in the braces and double-check the top rails.  The top rails can bow in or out so you need to run a string from each corner and correct any curves using the bracing.


The last step is to cut and tape the 4 inch foam pieces that will make up the insulation for the slab.  I am using the insulation to create the form.  The wood on the outside just supports the foam so that it does not collapse from the weight of the concrete.

Tonights Work Session

Last nights work session ended with me having all four sides on my slab constructed.  The corners are not nailed together yet as I still have a bit of leveling to  do in some places.

Once leveled, I will drive 2 foot pieces of 1/2 inch rebar every 2 feet around the perimeter to insure that the base stays in place as I construct the rest.

The four corner pieces you see are 23 inches from the ground (and just kind of sitting in place).  The final elevation will have the top boards 24 inches off the ground. I left these boards short so I would have some adjustment room for the top board.

With the rain we have had here recently my trenches have settled a bit and I need to find some fill to smooth out all the potholes.

Tonight’s Work Session

My lot contains a lot of sand and there are a couple former gravel pits that I will attempt to maneuver my tractor into.  Hopefully I Can come up with 20 yards or so of fill so I won’t need to pay someone to deliver it.

This Weekend

I have been buying materials every night on my drive home so I hope to have everything I need to complete the outside part of my forms on Saturday.

If all goes well Saturday, I will attempt to dig all the trenches for the plumbers on Sunday.  With a little luck I might be able to get a plumber on site next week.
Lightning Update

My new DSL modem is in and so it my Midnight Solar surge suppressor.  Last night I discovered that the telco network interface has a blown module.  I have ordered a new surge telephone surge suppressor from Amazon and will wire around the crap in the network interface.  It’s too much of a pain to have them come over….i’d rather just fix it myself.

Fortunately, I installed a cell phone repeater in the attic and it works well as a backup source of internet access.  The voice mode is pretty reliable, but the data side can be spotty and slow.  Its good enough in a pinch.

I’ll post a step by step install of the suppressor when I get a chance.

Lightning Protection for PV Systems

This morning I woke to a huge thunderstorm moving thru.  As I lay there listening to the thunder rumble, I began thinking that the roof of my XS house is constructed from 2×4’s and half inch plywood.  If a nearby tree gets hit any large branch is probably coming thru the roof.  I decided to go downstairs to sleep with the dog just in case.

At one point I saw a flash of light and heard a “pop” from someplace.  I decided to hit the main power disconnect…just in case.  A few minutes the same pop came back and I smelled “electronics”.  At that point I realized that my DSL modem was getting “hits” from the phone lines.  Of course it was too late my DSL modem was toast.  Growing up I remember our old phone would go “ding” for close lightning hits.  Not having a land line for the past 10 years I forgot about that.

I called Apu from Verizon and he said he will be sending me a new modem in two days (at no cost BTW…Good job Verizon).  When I left the house this morning it seemed like the phone line was not functioning.  I wonder if it will fix itself or if I may need to have someone visit me for service.

What about my PV panels?

This got me thinking that I should really add some surge protection to my PV panels and electrical box.  The wires from my panels are about 150 feet long and are strung up in trees and go all over the place…not very lightning proof I would say.

This morning I ordered a surge suppressor model MNSPD-115 from Midnight Solar.  Problem with surge protection is that there is a lot of bullshit floating around.  The bottom line with surge protection is that if God wants to take your DSL modem to heaven its going no matter how much surge protection you use.  Surge protection helps with nearby strikes that are conducted to your electronics through power lines or phone lines.

How does surge protection work?

In non-technical terms a surge suppressor is a very fast switch that closes when it sees too much voltage.  It is illustrated by this diagram:

Rodney the rodent when he is not eating propane tank hoses sits around and watches the voltage coming from your PV panels.  In the morning it starts out at a few volts and slowly rises to about 15 volts in full sunlight.  This pattern of voltage rising and falling each day is normal, so Rodney ignores it.

One day a thunderstorm comes along and sends a 500 volt spike down the PV wires heading towards your beloved PC.  Rodney swings into action and closes the switch which diverts this spike to your ground stake.  After the spike passes, Rodney opens the switch and your PC is safe (unless its a Windows machine).

If the spike was very large, then Rodney faithfully closes the switch.  Unfortunately the  switch melts down and Rodney winds up with a new job at the local chinese take out.  If the spike lasted long enough, then some of it would make it into your PC.  You then get to buy a new surge suppressor and PC (don’t worry its gone to a better place).

Where the manufacturer bullshit comes into play is how large of a spike Rodneys switch can handle before it melts down.  Sometimes Rodney costs too much and the manufacturer replaces him with Delmar who works, but not very fast or can’t read the volt meter very well due to poor eyesight.

Why did I pick this model?

MIdnight is the only company that has a video showing their product being tested in a real lab.  The video is on the product page.  Midnight has a very good reputation and based on the reading I have done seems to be the best for this kind of thing.

A Rodent Nearly Blew Me Up!

You may have heard that mice and other rodents can carry disease.  We all know that when it gets cold outside they begin looking for places to live in the crawl spaces of your house.  Well you can add another danger that these creatures pose to humans…death by gas explosion!

I woke Monday morning and went out to the deck.  At one point, I thought I caught a slight odor of gas.  I am pretty cautious about gas since my little house has 2 small tanks powering the grill and water heater.  I sniffed around the grill and sure enough the odor was coming from there.  As I got closer I began to hear a slight hissing sound of escaping gas.  Naturally I forgot to turn the tank off since I last used it and figured that the valve in my little Baby Q grill had given up.

As I turned the valve off on the tank I realized that the hissing sound was not coming from the grill but closer to the tank.  Upon closer examination I found this:

Something was gnawing on the “rubber” hose to my gas grill and almost blew me up!  This hose does not appear to be constructed of rubber but a PVC of some kind.  I will either have to get a better quality hose and/or put a jacket on it to protect against rodents.

I also made it a point to inspect the connection to my water heater which was still in good condition.  Everyone please check the hoses on your gas appliances!

Bodega Weekend Update

Lots of work on the bodega this weekend.  I managed to install my water line and get the base layer in for the slab.  As always it was a lot more work than I expected and I didn’t complete everything I wanted to.

Water line

Heavy rains made my trenches a sandy wet mess.  Of course wet sand weighs more than dry sand.  I spend a couple of hours digging out all the sections the backhoe missed (by hand).  mY goal was to keep the pipe 4ft below the surface and remove any rocks that might poke thru.  I then cut into my existing water line:

After removing sand from my shoes socks and everything else, I took a road trip to get some 1 inch XPS foam to cover the pipe.  Fortunately my lot has naturally occurring sandy pockets that are free from rocks.  I dug these sandy deposits out and covered the water pipe and laid the 1 inch foam over the pipe.  I then covered the foam with as much clean sand as I could scrape from the walls.

With the hard work out-of-the-way I spent the next 2 hours on the tractor moving 30+ yards of sand back into the trench.

Slab work

After double checking my slab elevation with the laser I marked out the areas that needed to be dug up for my gravel underbase.

I maneuvered my small tractor into position to loosen the dirt that needed to be removed.  I suspect that the dirt I removed would have made better slab base than the gravel I added.  Even with the tractor I spent a lot of time digging some of the hardest ground I have seen yet.

With the trenches dug, I moved about 7 yards of my bank gravel into position and ran the compactor over the trenches.  Here is the result of my days work:

I would say every spot on this footing is within one inch of being to the correct elevation.  I have another yard of gravel I will use to fill in the low spots.  I have a liquid level installed on one side of the slab (green clamps on the left), I just need to work my way around the perimeter.  I expect that another hour or two and I can start laying out my forms.

Lesson Learned

I learned a $90 lesson this week.  I needed 8 yards of bank run gravel delivered.  The gravel yard is not too far away so I phoned them and the lady told me the price was ~$150 delivered and I gave her a credit card.  The bill showed up in the mail and I learned that $90 of the bill was for delivery.  Had I known that I would have had them deliver a full truckload instead of 8 yards.  Lesson: Always ask about the delivery cost.
In my next post I will show you how my tiny house almost blew up!

Who is John Galt?

I went to visit the building inspector last night and had an epiphany.  Here in MA at least, we are living the novel Atlas Shrugged.  State regulations are stifling innovation and I don’t think they are keeping us safer or protecting the environment any better.  We’re just creating regulations because we have a machine that can manufacture them very quickly.

Building Permit

I have a building permit and can officially begin building my Bodega!  The inspector wants to see my slab before I pour concrete which I think is a pretty reasonable request.

I am shooting to be ready for a pour on the 25th of this month.  Lots of work still to do so I can be ready by then

I ordered 8 yards of bank run gravel for the slab this morning.  Total cost $159 not too bad I would say.  I’ll be renting a plate compactor Saturday afternoon for $85/24 hours.  So the logistics of this weekends work are in place.


The plumbing inspector was in the office last night so I took a few minutes to speak with him to see what I could learn.  Speaking with the him is what has me all riled up today.  Our inspector is a nice guy and was very helpful (he really was).  The state of MA makes the rules he has to live by and he really has no say in the matter.

I want to install two generators in a steel enclosure for AC power.  I want those generators to run from propane or gas.  I learned that in order for the inspector to approve the installation for propane, the item that the propane is connected to must be approved by the state!

Do you really think that a propane conversion kit for a Honda generator has been approved by MA…I doubt it.  Bottom line is that I cannot legally run a Honda EU2000i generator from a 500 gallon propane tank in MA.

It seems to me that this sort of thing actually causes homeowners to be less safe.  In this situation I have 5 choices:

  1. Hook up the generators myself
  2. Run the generators from a 20 pound propane tank
  3. Install a gas grill connector and then connect the generator to that (secretly)
  4. Buy a MA approved generator
  5. Forget using propane for my generator

Option 1 puts me at risk of blowing myself up.  Option 2 would have a propane tank three feet from a hot running generator.  Option 3 is probably the one I will have to use.  Option 4 and 5 are totally out of the question.


So two out of the three viable options have me running my generator in a manner that is less than optimal.  I conclude that these laws don’t make us safer at all….there must be some other reason they exist…maybe I should follow the money.

Mini Update

Not much to report today.  Last night I dug out the last bit of the trench for the water line without mauling my electrical wires or the pipe.  Several weeks ago I installed 200 feet of pipe and wire to my XS house so it would have water.  The pipe I will install for the Bodega will be teed off of this line.  I will need to cap the end so that I can still get water to the XS house.  At some point I may install a hose connection to this end so I can have water for construction.  Tonight if I get time I will try to clean up the bottom of the trench so I can install the pipe on Saturday with little digging.

Its important in the cold climates to remove any rocks near underground piping.  When things freeze the pointy parts of rocks can unexpectedly puncture your pipe.  To prevent this I will be using native material (which is very nice sand) and sift out the rocks with a homemade 1/2 inch box siifter.

Once the pipe is laid and is covered in sand, I will add a layer of one inch XPS foam sheating over it.  The foam sheating adds a bit of freeze resistance and protection from rocks in the soil that I lay on top of the pipe.


Last week I was not able to pick up my building permit, hopefully I will be able to get it tonight.