Section 5.8.1

It is not obviously clear why the chamber is called "The Queen´s Chamber", as there are no traces or hints referring to any queen. Anyway, there is a global consensus to call the chamber "The Queen´s Chamber", so I do it as well. 

The chamber is empty, it has an angular roof and the eastern wall has niche with four overlappings.

The walls, roof and niche is made of fine white limestone, which is not a part of the masonry in general. The floor is a part of the masonry, very rough and uneven. The chamber has no "real floor" and has the same level as the lower part of the floor in the horizontal passageway. 

The greater part of the walls is covered with salt incrustation, which made it hard to find clear joints between the stones. The joints are filled with cement, which is common in the masonry.  

Source: The Great Pyramid Passages And Chambers" Volume 1 by John and Morton Edgar, 1910 , (page 296)

It looks like the northern and the eastern parts of the niche have been "examined" in a destructive way. 

Section 5.8.2

Source: The Great Pyramid Passages And Chambers" Volume 1 by John and Morton Edgar, 1910 , (page 53)

Here is another drawing made by Edgar showing the chamber towards East: 

Source: The Great Pyramid Passages And Chambers" Volume 1 by John and Morton Edgar, 1910 , (page 70)

The two channels are also shown leading or pointing to the outside of the pyramid.

Section 5.8.3

Source: The Great Pyramid Passages And Chambers" Volume 1 by John and Morton Edgar, 1910 , (page 298)

Section 5.8.4

As you can see, the Queen´s chamber is the only (known) chamber in the Great Pyramid which is located exactly in the midline of the south-north direction. 

Petrie did the same observation and added some measures:

"41. In the Queen's Chamber it seems, from the foregoing statement, that the ridge of the roof is exactly in the mid-place of the Pyramid, equidistant from N. and S. sides ; it only varies from this plane by a less amount than the probable error of the determination.

The size of the chamber (after allowing suitably in each part for the incrustation of salt) is on an average 205,85 wide, and 226,47 long, 184,47 high on N. and S. walls, and 245,1 high to the top of the roof ridge on E. and W. walls. The variations of the horizontal quantities in detail are as follows, from the mean dimensions."

(S5orig-[S41]-P66-L29-37)

My comments:
The above mentioned measures are in British inches.
205,85" = 9,98 cubits RM (average) wide, which equals 100 pixels. (The nominal measure might have been 10 cubits NM).
226,47" = 10,98  cubits RM (average) long , which equals 110 pixels.  (The nominal measure might have been 11 cubits NM).
184,47" = 8,95  cubits RM (average) high on northern and southern walls, which equals 90 pixels. (The nominal measure might have been 9 cubits NM).
245,1"    = 11,89  cubits RM (average) high to the top of the roof ridge, which equals 119 pixels.  (The nominal measure is unknown).

Petrie measured the angled roof stones as well:

(S5orig-[S42]-P69-L10-12)

My comments:
The mentioned sloping calculated lengths are in  British inches.

Northern side:

120,00" = 5,82 cubits, east end on north side.
119,96" = 5,82 cubits, west end on north side.

Average = 5,82 cubits on northern side.

Southern side:
119,12" = 5,78 cubits, east end on south side. 

118,59" = 5,75 cubits , west end on south side.

Average = 5,76 cubits on southern side.

The angles:

Northern side:

30° 48´ = 30,80° , east end on north side.

30° 14´ = 30,23° , west end on north side.

Average = 30,52° on northern side.

Southern side:

30° 33´ = 30,55° , east end on south side.

30° 10´ = 30,17° , west end on south side.

Average = 30,36° on northern side.

Here is a drawing with the measures:

The lengths are in cubits RM average.

The lengths in parenthesis are calculated values:

5,76 cubits RM average x cos 30,36° = 4,97 cubits.  
5,82 cubits RM average x cos 30,52° = 5,01 cubits.