That looks really good Peter. I think your's is a lot more practical than mine. The one I'm building is just under 2m wide (6 foot), 0.6m deep (2 foot) and about 1.2m high at the front (4 foot). It will hold two layers of logs. How long does your store of logs last? I think this one will take about 60% of yours. What size wood did you use for the frame?
The difference between yours and mine seems to be the height only. We use up about half of the store per winter. Mostly to have a cosy fire and at times to add to the house heating.
The floor part is made from a frame of 125x50 mm (5"x2") with three feet at the front to get about 20 cm (8") of clearance to the ground. The rear frame is secured to the house, in this case my garage. Between fromnt and rear I have 125x50 braces on top of which i put 75x25 (3"x2") floor boards with about 25 mm (1") spaces for ventilation.
Then I made a simple frame from 50x50 (2"x2") at the front and rear corners, as well as in the middle. The rear corner piees were secured to the garage as the bottom frame. Betwseen the corner posts I put braces with a distance of about 60 cm (two feet) to form kind of a ladder on each side. I replicated the roof angle from the garage, still using 50x50 for the framing.
At this point I took a spade drill and drilled I think five holes evenly through the middle "ladder" and using "broom sticks" it became like a fence to separate the two sides of the store. That done finished the framework.
Next up was to cover the roof with ordinary cheap boards or planks about 20x100 (1"x4") onto which I put some roof tar felt. When I made the roof I nowadays think I made a little too small overhang at the front. A little more would have protected the log ends better. After the roof came the sides which is the same type of panel as on the house. Bottom layer is 25x150mm (1"x6") with a 50 mm (2") gap. The gap is then covered with a 25x100 (1"x4") board as a lid. The construction ventilates the panel extremely well. Then the last bit was to finish with trimmings around corners, under the roof edges and the opening. Finally painted to match.
I like the idea of standing bars in the middle
and will think about how to do this. The "floorboards" are to have gaps for good circulation of air like yours. I need to think about whether or not to put roofing felt/tar paper in, however the shingles all overlap so seem to work well to keep the rain out.
Where I live many people have more money than sense so tend to have articles that look nice, rather than being practical. In a way this is an "Arts and Crafts" style project.
The lady next door has seen similar stores in shops but they are not as strong as mine. She says they flex when you push them. My design is a "Space Frame" with" triangulated Braces". I can stand on the roof with no problems and I weigh 92kg (14.5 stone or 200 pounds). You could probably park a car on it (or maybe a motorbike).
Mind you, the cost of the wood alone so far is more than buying a new log store from the shops, If I were to be charging labour it would end up 6 times as much!!!
Even though I have not used very heavy material, the strength of the total construction is really good. I can easily stand on the roof, something I dod when changing the roof tiles on the garage.
Our wood burning stove is a moderna construction with a traditional design as shown in this link:
http://www.keddy.se/kaminer/latta-murspisar/carisma-2(Unfortunately the text is in swedish so you have to use the translate button, but it really is a plate cassette inserted into a reinforced concrete case. It is light enough to stand directly onto a standard floor and does not get very hot on the outside. It includes a fan in the bottom that createes an airflow around the cassette and chimney pipe and blows the hot air out into the room through the black ventilator a bit up the chimney. The air for the fire is taken from the outside in a separate flow so as not to use up the hot indoor air. It is very economical and stores its heat from late evening and is still luke warm in the morning.
Such a cassette would perhaps be a good solution to add to your open fireplace for better "fuel economy".
Nice to read and see others solutions as well. Variations on a theme so to say

BR
/Peter