The south facing exterior wall provides the facade to the mastaba. All external engravings are in sunken relief.

At its western side is a reasonably well preserved temenos wall of a single course of blocks, capped with rounded stones, forming a small courtyard to the mastaba. The wall, is extensively decorated on the outer face (south and west facing) with repeating engraved images of Mereruka, preceded in each case with 3 columns of text (). The decoration currently consists of 21 groups, 5 on the west facing section of the wall and 16 on the part facing south. This wall (including some loose, non-positioned blocks) lists 44 (more if the repeated ones are not ignored) of Mereruka's known 84 titles. The texts are all in the form (right to left) : column 1 - his titles, column 2 - "revered by" followed by a named god, column 3 - his two names. The west end of the south facing wall finishes with two columns of text in the same form as columns 2 and 3 of those preceding the images. Enclosed within its western end is an offering place for one of Mereruka's sons, Khenu, comprising an offering table, on which stands a large boxed enclosure with a false door at its rear; all are inscribed, however only the lower portion now survives ().

The extreme east and west () ends of the mastaba's facade are engraved with seated figures of Mereruka. Other figures of him are engraved on the east and west walls at the same corners, all face in the direction of the entrance.

The section of the south facing facade containing the actual entrance, door posts and lintel, is inset by about 0.25m. The inset area extends to the full height of the mastaba and is approx. 4m wide.
On either side of the tall narrow entrance (approx 1.0m wide, 2.7m high to the lintel) are standing figures of the deceased, in front of whom stands (at a much smaller scale) his wife Watetkhethor (). The images face the doorway, separated from it by two columns of text, with four more rows positions above his head. These, as usual, give his name an titles. Most of the inscription of the corniced lintel has been weathered away along with most of the lintel itself.
The decoration continues (westwards) behind the left-hand standing figure with the lower remaining portion of six columns of a biographical inscription (). Originally a similar set of columns almost certainly existed behind the figure on the other side of the doorway.
The biographical text delimits the extent of the inset area of the facade. However, the decoration continues further on the western side (and probably originally to the east) with another standing figure of Mereruka (again see ). On the lower portion remains, but from the delimiting lines at the left-hand side, it is almost certain that nothing beyond this existed, until the decoration at the extreme corners of the front facade.

The inner thicknesses of the doorway (0.6m wide) each contain smaller standing images of Mereruka (), above which are four more columns of inscribed text. Spanning the top of the narrow gap between the inner walls of the doorway, before the wider entrance passage to chamber 1, is a rounded spar whose inscription has now worn away.

Beyond the doorway, a short passage gives entry into chamber A1 (the vestibule). Although the passage maintains the south-north axis, the chamber is oriented along a west-east axis, the entry passage being at the west end of the south wall. The chamber is approximately 7.0m long, 2.7m wide and, like all of the other chambers, it is about 4.2 metres in height. As with many walls in the mastaba, only the lower half has survived intact, with the addition of a few upper blocks of the north and south walls.

The east (right-hand) side of the entrance passageway is decorated as a separate entity, whilst the west side is continuous with the west wall of this first chamber and will be described as such.
The east wall (approx. 1.2m wide) contains an unusual image of Mereruka seated in front of an easel, with a brush in his right hand and a paint palette over his shoulder. He is painting the three seasons of the Egyptian year (). They are shown in the form of three seated characters, each holding a cartouche enclosing four hieroglyphic crescent moons (the sign for "month") ; thus they symbolically represent the four months of each season. Starting at the end furthest from Mereruka, they are the seasons of : inundation (Akhet), accompanied by the hieroglyphic sign for "good" (nefer) ; germination (Peret), along with the sign for "offering" (hetep) ; finally, summer (Shemu), and the sign for "life" (ankh).
The indication is of Mereruka looking out from his tomb, painting whilst viewing the annual cycle of Egyptian life.
Forward of Mereruka, and in a smaller separate panel facing him, stands "His son, lector-priest and scribe of the God's Book, Khenu", his instruments in his hand.

This wall is a continuation of the west entrance passage wall. It shows the tall figure of Mereruka striding towards the interior of the tomb, accompanied by the much smaller figures of his wife Watetkhethor (behind him) and his eldest son Meryteti (in front). On either side of the central group are groups of three attendants placed above each other. Nine still exist in front but only six behind.
At the northern end of this wall is the entrance to chambers of Watetkhethor's section of the mastaba.

The two long north and south walls are decorated with complementing scenes set in marshes filled with wild life. Each side is set on a stretch of horizontal water teaming with a variety fish, large hippopotami and dangerous crocodiles, all drawn with no regard to scale, but with an anatomical precision leaving no doubt to the identity of the fish species. Of particular interest is the broad stretch of water (shown vertically) on the north wall ().
The lower registers of each wall still exists, but the imagery of Mereruka is more fully preserved on the south wall, showing his head and extended left arm (). On both walls Mereruka is shown accompanied by his wife in a light papyrus skiff and in both cases they face towards the entrance to the inner chambers.
On the north wall Mereruka is fishing with a harpoon. The characters of the accompanying sub-registers participate by hunting the hippopotamus, while other men carry fish in baskets (see opposite, and ).
This wall contains the longest surviving list of Seshseshet's titles. However, even though the upper portions of the seven columns is lost (see ), these can still be translated with reasonable accuracy). "King's daughter of (his) body (…) by her father, his beloved, priestess of Hathor, Lady of the Sycamore (…), (she) who does what (…) desires, honoured one by the Great God, Lord of the West (…) Osiris, Lord of Busiris, honoured one by Anubis, he who is upon his hill (…) who is in front of the Divine Booth (…) Western necropolis (…), Watetkhethor, her beautiful name is Seshseshet.".
On the south wall he is in the act of launching his throwing stick at a flock of waterfowl, which take flight from the thicket of reeds. This time in the lower register, immediately below the reeds, hippos are attacked by crocodiles (). Towards the left, cattle are herded through the water, above which other men wrestle to control other cattle (, and ) ; the text above them, on the left, states: "Oh herdsman! May you be watchful against that aquatic animal, which is in the water, and which comes as an invisible one. Pay great attention to him."; and on the right: "Row, hurry, comrade." and "Herdsmen, on the water.". Above the scenes with cattle, men water and tend plants, in what can only be a cultivated area (perhaps a garden). Further up still is the transport of fowl in cages ().
It is uncertain whether these are leisure activities or whether they have some other significance.

At the end of this vestibule, the east wall offers the sight of a tall figure of the owner and one of almost equal size of his wife ( and ). Their heads are missing, but they can be seen holding hands, a loving feature which reveals their closeness and is repeated more than once in the tomb, with subtle variations. The couple face north, heading with due ceremony towards the depths of the main chambers. They are preceded, on six sub-registers, by various servants and porters of a palanquin. After the completion of the decoration of this wall it was cut at its northern end to accept an entrance passageway in to chamber A2, destroying the southern part of the lower three sub-registers of servants.

The chamber is approximately 2.5m (west-east) by 2.1m. The entrance passageway is only about 2m high, with a width of 0.6m and a depth of 0.75m. Its floor is higher than that of the rest of the tomb. The walls of the passageway and the chamber were left undecorated; the surface stone was even left undressed.
This chamber may have been added later purely to make use of what had been a corner of solid masonry. According to Daressy, this chamber was built above a four metre deep well shaft, in which were found only remains of alabaster and terra cotta vases.